Thermostat with multiple sensing systems integrated therein

ABSTRACT

A thermostat may include a proximity sensor and a temperature sensor. The thermostat may also include a sensor mount assembly containing the proximity sensor, the temperature sensor, and a first alignment feature. The thermostat may additionally include a lens assembly having a first area, a second area, and a second alignment feature, where the second area includes a Fresnel lens, and the first area is thinner than the second area. The thermostat may further include a front cover where the outward-facing surface of the lens assembly is shaped to continuously conform to a curvature of the front cover. The thermostat may also include a frame member with third and fourth alignment features configured for respective matable alignment with the first and second alignment features and configured such that the proximity sensor and the temperature sensor are maintained in generally close, non-touching proximity to the lens assembly, the first area of the lens assembly being aligned with the proximity sensor, and the second area of the lens assembly being aligned with the temperature sensor.

BACKGROUND

Microprocessor controlled “smart” thermostats may have advancedenvironmental control capabilities that can save energy while alsokeeping occupants comfortable. To do this, these smart thermostatsrequire more information from the occupants as well as the environmentswhere the thermostats are located. These thermostats may also be capableof connection to computer networks, including both local area networks(or other “private” networks) and wide area networks such as theInternet (or other “public” networks), in order to obtain current andforecasted outside weather data, cooperate in so-called demand-responseprograms (e.g., automatic conformance with power alerts that may beissued by utility companies during periods of extreme weather), enableusers to have remote access and/or control thereof through theirnetwork-connected device (e.g., smartphone, tablet computer, PC-basedweb browser), and other advanced functionalities. Of particularimportance is the ability to accurately assess the state of occupancy ofa home and to provide a meaningful, yet simple user interface forresponding to user inputs.

BRIEF SUMMARY

In some embodiments, a thermostat may include a proximity sensor fordetecting user presence and a temperature sensor that providestemperature measurements for calculating an ambient temperature in anarea surrounding the thermostat. The thermostat may also include asensor mount assembly containing the proximity sensor and thetemperature sensor, where the sensor mount assembly includes a firstalignment feature. The thermostat may additionally include a lensassembly including a first area, a second area, and a second alignmentfeature, where the second area includes a Fresnel lens, and the firstarea is thinner than the second area. The thermostat may further includea front cover, where an outward-facing surface of the lens assembly isshaped to continuously conform to a curvature of the front cover. Thethermostat may also include a frame member comprising third and fourthalignment features configured for respective matable alignment with thefirst and second alignment features and further configured such that theproximity sensor and the temperature sensor are maintained in generallyclose, non-touching proximity to the lens assembly, the first area ofthe lens assembly being aligned with the proximity sensor, and thesecond area of the lens assembly being aligned with the temperaturesensor.

In some embodiments, a method of aligning sensor and lens elements in asmart thermostat may include providing a sensor mount assembly thatincludes a proximity sensor for detecting user presence, a temperaturesensor that provides temperature measurements for calculating an ambienttemperature in an area surrounding the thermostat, and a first alignmentfeature. The method may also include providing a lens assembly thatincludes a first area, a second area comprising a Fresnel lens where thefirst area is thinner than the second area, and a second alignmentfeature. The method may additionally include providing a frame membercomprising third and fourth alignment features configured for respectivematable alignment with the first and second alignment features andfurther configured such that the proximity sensor and the temperaturesensor are maintained in generally close, non-touching proximity to thelens assembly, the first area of the lens assembly being aligned withthe proximity sensor, and the second area of the lens assembly beingaligned with the temperature sensor. The method may also includeconnecting the sensor mount assembly to the frame member by mating thefirst alignment feature with the third alignment feature, and connectingthe lens assembly to the frame member by mating the second alignmentfeature with the fourth alignment feature.

Some embodiments may include one or more of the following features inany combination and without limitation. The sensor mount assembly mayinclude a flexible circuit board to which the proximity sensor and thetemperature sensor are mounted. The sensor mount assembly may include abracket comprising at least two different elevations such that theproximity sensor and the temperature sensor sit at the at least twodifferent elevations relative to the lens. The temperature sensor mayinclude an IC body and a metal pin through which the temperaturemeasurements for calculating the ambient temperature in the areasurrounding the thermostat are received, where a portion of the sensormount assembly is rotated at an angle such that the metal pin is closerto the lens assembly than the IC body. The sensor mount assembly mayinclude a second proximity sensor. The proximity sensor may include apassive infrared (PIR) sensor, and the distance between the second areaof the lens assembly and the PIR sensor may be between 6 mm and 8 mm.The lens assembly may be fabricated from a continuous piece ofhigh-density polyethylene (HDPE) using an injection molding process. Theproximity sensor may include a multi-channel thermopile comprising atleast a left channel and a right channel. The distance between thetemperature sensor and the first area of the lens may be less than 3 mm.The thermostat may also include electromagnetic shielding that wrapsaround the proximity sensor and around at least a portion of the sensormount assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a smart home environment within whichone or more of the devices, methods, systems, services, and/or computerprogram products described further herein can be applicable.

FIG. 2 illustrates a network-level view of an extensible devices andservices platform with which the smart home of FIG. 1 can be integrated,according to some embodiments.

FIG. 3 illustrates an abstracted functional view of the extensibledevices and services platform of FIG. 2, according to some embodiments.

FIG. 4 illustrates a schematic diagram of an HVAC system, according tosome embodiments.

FIG. 5A-5D illustrate a thermostat having a visually pleasing, smooth,sleek and rounded exterior appearance while at the same time includingone or more sensors for detecting occupancy and/or users, according tosome embodiments.

FIG. 6A-6B illustrate exploded front and rear perspective views,respectively, of a thermostat with respect to its two main components,according to some embodiments.

FIG. 6C-6D illustrate exploded front and rear perspective views,respectively, of a head unit with respect to its primary components,according to some embodiments.

FIG. 6E-6F illustrate exploded front and rear perspective views,respectively, of a head unit display assembly with respect to itsprimary components, according to some embodiments.

FIG. 6G-6H illustrate exploded front and rear perspective views,respectively, of a back plate unit with respect to its primarycomponents, according to some embodiments.

FIG. 7 illustrates a block diagram illustrating circuitry within athermostat, according to some embodiments.

FIGS. 8A-8H illustrate various views of the sensor flex assembly.

FIG. 9 illustrates a view of the PIR, the bracket, and the flexiblecircuit board as they are assembled to form the sensor flex assembly.

FIGS. 10A-10B illustrate conductor patterns on the flexible circuitboard to isolate the temperature sensor from internal heating effects.

FIGS. 10C-10D illustrate the components layout on the flexible circuitboard to isolate the temperature sensor from internal heating effects.

FIGS. 11A-E illustrates various views of a multifunction lens element.

FIG. 12 illustrates a near-field proximity sensor range and a far-fieldproximity sensor range, according to some embodiments.

FIG. 13 illustrates a diagram of movements perpendicular to the plane ofthe smart-home device, according to some embodiments.

FIG. 14 illustrates sample horizontal paths that may be detected by thesmart-home device using a threshold, according to some embodiments.

FIG. 15 illustrates an example of a diagonal path towards the smart-homedevice, according to some embodiments.

FIG. 16 illustrates the four-channel viewing areas of a near-fieldproximity sensor, according to some embodiments.

FIG. 17 illustrates a characteristic response of a digital filterdesigned to filter the output response of the near-field proximitysensor.

FIG. 18 illustrates a flowchart of a method for detecting a userapproach to a smart-home device, according to some embodiments.

FIG. 19 illustrates a flowchart of a method for continuously processinga motion signature after the smart-home device initiates a responsiveaction, according to some embodiments.

FIG. 20 illustrates a second mode of operation for the near-fieldproximity sensor during a user interactive session, according to someembodiments.

FIG. 21 illustrates a flowchart of a method for interpreting andgestures using the multi-channel proximity sensor, according to someembodiments.

FIG. 22 illustrates using data from more than one smart-home device totrack user movements, according to some embodiments.

FIG. 23 illustrates a diagram of different user positions relative to asmart-home device, according to some embodiments.

FIG. 24 illustrates a flowchart of a method for generating andtransitioning between various graphical displays on a user interface ofa smart-home device, according to some embodiments.

FIG. 25A illustrates an example of a near-field display of a thermostatfunction, according to some embodiments.

FIG. 25B illustrates an example of a far-field display of the thermostatfunction, according to some embodiments.

FIG. 26A illustrates an example of a near-field display of a clockfunction, according to some embodiments.

FIG. 26B illustrates an example of a far-field display of the clockfunction, according to some embodiments.

FIG. 27A illustrates an example of a near-field display of an alertfunction, according to some embodiments.

FIG. 27B illustrates a near-field display of the alert function,according to some embodiments.

FIG. 28 illustrates a flowchart of a method of using characteristics ofuser motion to generate and control user interface displays, accordingto some embodiments.

FIG. 29 illustrates a diagram of a progressive alert display, accordingto some embodiments.

FIG. 30 illustrates a diagram of a progressive user interface based onuser identities, according to some embodiments.

FIG. 31 illustrates a diagram of progressive user displays based on uservelocities, according to some embodiments.

FIGS. 32A-32D illustrate user interface displays that are part of aprogressive animation that may be displayed when the user interface isactivated, according to some embodiments.

DETAILED DESCRIPTION OF THE INVENTION

The subject matter of this patent specification relates to the subjectmatter of the following commonly assigned applications, filed on thesame day as the present application, each of which is incorporated byreference herein:

-   -   U.S. patent application Ser. No. 14/836,699, filed on Aug. 26,        2015, titled THERMOSTAT WITH MULTIPLE SENSING SYSTEMS INTEGRATED        THEREIN, to Stefanski et al.    -   U.S. patent application Ser. No. 14/836,648, filed on Aug. 26,        2015, titled THERMOSTAT WITH MULTIPLE SENSING SYSTEMS INCLUDING        PRESENCE DETECTION SYSTEMS INTEGRATED THEREIN, to Goyal et al.    -   U.S. patent application Ser. No. 14/836,568, filed on Aug. 26,        2015, titled AUTOMATED DISPLAY ADJUSTMENTS FOR SMART-HOME DEVICE        BASED ON VIEWER LOCATION OR OTHER SENSED VIEWER-RELATED        PARAMETERS, to Goyal et al.    -   U.S. patent application Ser. No. 14/836,744, filed on Aug. 26,        2015, titled SMART THERMOSTAT ROBUST AGAINST ADVERSE EFFECTS        FROM INTERNAL HEAT-GENERATING COMPONENTS, to Stefanski et al.    -   U.S. patent application Ser. No. 14/836,660, filed on Aug. 26,        2015, titled THERMOSTAT ELECTRONIC DISPLAY AND LENSING ELEMENT        THEREFOR, to Giustina.    -   U.S. patent application Ser. No. 14/836,631, filed on Aug. 26,        2015, titled ROTATION DETECTION FOR RING-SHAPED USER INPUT        MEMBER OF SMART-HOME DEVICE, to Stefanski et al.    -   U.S. patent application Ser. No. 14/836,595, filed on Aug. 26,        2015, titled USER INTERFACE MEMBER FOR ELECTRONIC DEVICE, to        Giustina et al.    -   U.S. patent application Ser. No. 14/836,323, filed on Aug. 26,        2015, titled INTEGRATED ANTENNA SYSTEM AND RELATED COMPONENTS        MANAGEMENT FOR A SMART THERMOSTAT, to Honjo et al.        The above-referenced patent applications are collectively        referenced herein as “the commonly assigned incorporated        applications.”        The Smart-Home Environment

A detailed description of the inventive body of work is provided herein.While several embodiments are described, it should be understood thatthe inventive body of work is not limited to any one embodiment, butinstead encompasses numerous alternatives, modifications, andequivalents. In addition, while numerous specific details are set forthin the following description in order to provide a thoroughunderstanding of the inventive body of work, some embodiments can bepracticed without some or all of these details. Moreover, for thepurpose of clarity, certain technical material that is known in therelated art has not been described in detail in order to avoidunnecessarily obscuring the inventive body of work.

As used herein the term “HVAC” includes systems providing both heatingand cooling, heating only, cooling only, as well as systems that provideother occupant comfort and/or conditioning functionality such ashumidification, dehumidification and ventilation.

As used herein the terms power “harvesting,” “sharing” and “stealing”when referring to HVAC thermostats all refer to thermostats that aredesigned to derive power from the power transformer through theequipment load without using a direct or common wire source directlyfrom the transformer.

As used herein the term “residential” when referring to an HVAC systemmeans a type of HVAC system that is suitable to heat, cool and/orotherwise condition the interior of a building that is primarily used asa single family dwelling. An example of a cooling system that would beconsidered residential would have a cooling capacity of less than about5 tons of refrigeration (1 ton of refrigeration=12,000 Btu/h).

As used herein the term “light commercial” when referring to an HVACsystem means a type of HVAC system that is suitable to heat, cool and/orotherwise condition the interior of a building that is primarily usedfor commercial purposes, but is of a size and construction that aresidential HVAC system is considered suitable. An example of a coolingsystem that would be considered residential would have a coolingcapacity of less than about 5 tons of refrigeration.

As used herein the term “thermostat” means a device or system forregulating parameters such as temperature and/or humidity within atleast a part of an enclosure. The term “thermostat” may include acontrol unit for a heating and/or cooling system or a component part ofa heater or air conditioner. As used herein the term “thermostat” canalso refer generally to a versatile sensing and control unit (VSCU unit)that is configured and adapted to provide sophisticated, customized,energy-saving HVAC control functionality while at the same time beingvisually appealing, non-intimidating, elegant to behold, anddelightfully easy to use.

FIG. 1 illustrates an example of a smart home environment within whichone or more of the devices, methods, systems, services, and/or computerprogram products described further herein can be applicable. Thedepicted smart home environment includes a structure 150, which caninclude, e.g., a house, office building, garage, or mobile home. It willbe appreciated that devices can also be integrated into a smart homeenvironment that does not include an entire structure 150, such as anapartment, condominium, or office space. Further, the smart homeenvironment can control and/or be coupled to devices outside of theactual structure 150. Indeed, several devices in the smart homeenvironment need not physically be within the structure 150 at all. Forexample, a device controlling a pool heater or irrigation system can belocated outside of the structure 150.

The depicted structure 150 includes a plurality of rooms 152, separatedat least partly from each other via walls 154. The walls 154 can includeinterior walls or exterior walls. Each room can further include a floor156 and a ceiling 158. Devices can be mounted on, integrated with and/orsupported by a wall 154, floor or ceiling.

The smart home depicted in FIG. 1 includes a plurality of devices,including intelligent, multi-sensing, network-connected devices that canintegrate seamlessly with each other and/or with cloud-based serversystems to provide any of a variety of useful smart home objectives.One, more or each of the devices illustrated in the smart homeenvironment and/or in the figure can include one or more sensors, a userinterface, a power supply, a communications component, a modularity unitand intelligent software as described herein. Examples of devices areshown in FIG. 1.

An intelligent, multi-sensing, network-connected thermostat 102 candetect ambient climate characteristics (e.g., temperature and/orhumidity) and control a heating, ventilation and air-conditioning (HVAC)system 103. One or more intelligent, network-connected, multi-sensinghazard detection units 104 can detect the presence of a hazardoussubstance and/or a hazardous condition in the home environment (e.g.,smoke, fire, or carbon monoxide). One or more intelligent,multi-sensing, network-connected entryway interface devices 106, whichcan be termed a “smart doorbell”, can detect a person's approach to ordeparture from a location, control audible functionality, announce aperson's approach or departure via audio or visual means, or controlsettings on a security system (e.g., to activate or deactivate thesecurity system).

Each of a plurality of intelligent, multi-sensing, network-connectedwall light switches 108 can detect ambient lighting conditions, detectroom-occupancy states and control a power and/or dim state of one ormore lights. In some instances, light switches 108 can further oralternatively control a power state or speed of a fan, such as a ceilingfan. Each of a plurality of intelligent, multi-sensing,network-connected wall plug interfaces 110 can detect occupancy of aroom or enclosure and control supply of power to one or more wall plugs(e.g., such that power is not supplied to the plug if nobody is athome). The smart home may further include a plurality of intelligent,multi-sensing, network-connected appliances 112, such as refrigerators,stoves and/or ovens, televisions, washers, dryers, lights (inside and/oroutside the structure 150), stereos, intercom systems, garage-dooropeners, floor fans, ceiling fans, whole-house fans, wall airconditioners, pool heaters 114, irrigation systems 116, security systems(including security system components such as cameras, motion detectorsand window/door sensors), and so forth. While descriptions of FIG. 1 canidentify specific sensors and functionalities associated with specificdevices, it will be appreciated that any of a variety of sensors andfunctionalities (such as those described throughout the specification)can be integrated into the device.

In addition to containing processing and sensing capabilities, each ofthe devices 102, 104, 106, 108, 110, 112, 114 and 116 can be capable ofdata communications and information sharing with any other of thedevices 102, 104, 106, 108, 110, 112, 114 and 116, as well as to anycloud server or any other device that is network-connected anywhere inthe world. The devices can send and receive communications via any of avariety of custom or standard wireless protocols (Wi-Fi, ZigBee,6LoWPAN, Thread, Bluetooth, BLE, HomeKit Accessory Protocol (HAP),Weave, etc.) and/or any of a variety of custom or standard wiredprotocols (CAT6 Ethernet, HomePlug, etc.). The wall plug interfaces 110can serve as wireless or wired repeaters, and/or can function as bridgesbetween (i) devices plugged into AC outlets and communicating usingHomeplug or other power line protocol, and (ii) devices that not pluggedinto AC outlets.

For example, a first device can communicate with a second device via awireless router 160. A device can further communicate with remotedevices via a connection to a network, such as the Internet 162. Throughthe Internet 162, the device can communicate with a central server or acloud-computing system 164. The central server or cloud-computing system164 can be associated with a manufacturer, support entity or serviceprovider associated with the device. For one embodiment, a user may beable to contact customer support using a device itself rather thanneeding to use other communication means such as a telephone orInternet-connected computer. Further, software updates can beautomatically sent from the central server or cloud-computing system 164to devices (e.g., when available, when purchased, or at routineintervals).

By virtue of network connectivity, one or more of the smart-home devicesof FIG. 1 can further allow a user to interact with the device even ifthe user is not proximate to the device. For example, a user cancommunicate with a device using a computer (e.g., a desktop computer,laptop computer, or tablet) or other portable electronic device (e.g., asmartphone). A webpage or app can be configured to receivecommunications from the user and control the device based on thecommunications and/or to present information about the device'soperation to the user. For example, the user can view a current setpointtemperature for a device and adjust it using a computer. The user can bein the structure during this remote communication or outside thestructure.

The smart home also can include a variety of non-communicating legacyappliances 140, such as old conventional washer/dryers, refrigerators,and the like which can be controlled, albeit coarsely (ON/OFF), byvirtue of the wall plug interfaces 110. The smart home can furtherinclude a variety of partially communicating legacy appliances 142, suchas IR-controlled wall air conditioners or other IR-controlled devices,which can be controlled by IR signals provided by the hazard detectionunits 104 or the light switches 108.

FIG. 2 illustrates a network-level view of an extensible devices andservices platform with which the smart home of FIG. 1 can be integrated,according to some embodiments. Each of the intelligent,network-connected devices from FIG. 1 can communicate with one or moreremote central servers or cloud computing systems 164. The communicationcan be enabled by establishing connection to the Internet 162 eitherdirectly (for example, using 3G/4G connectivity to a wireless carrier),though a hubbed network (which can be scheme ranging from a simplewireless router, for example, up to and including an intelligent,dedicated whole-home control node), or through any combination thereof.

The central server or cloud-computing system 164 can collect operationdata 202 from the smart home devices. For example, the devices canroutinely transmit operation data or can transmit operation data inspecific instances (e.g., when requesting customer support). The centralserver or cloud-computing architecture 164 can further provide one ormore services 204. The services 204 can include, e.g., software update,customer support, sensor data collection/logging, remote access, remoteor distributed control, or use suggestions (e.g., based on collectedoperation data 204 to improve performance, reduce utility cost, etc.).Data associated with the services 204 can be stored at the centralserver or cloud-computing system 164 and the central server orcloud-computing system 164 can retrieve and transmit the data at anappropriate time (e.g., at regular intervals, upon receiving requestfrom a user, etc.).

One salient feature of the described extensible devices and servicesplatform, as illustrated in FIG. 2, is a processing engines 206, whichcan be concentrated at a single server or distributed among severaldifferent computing entities without limitation. Processing engines 206can include engines configured to receive data from a set of devices(e.g., via the Internet or a hubbed network), to index the data, toanalyze the data and/or to generate statistics based on the analysis oras part of the analysis. The analyzed data can be stored as derived data208. Results of the analysis or statistics can thereafter be transmittedback to a device providing ops data used to derive the results, to otherdevices, to a server providing a webpage to a user of the device, or toother non-device entities. For example, use statistics, use statisticsrelative to use of other devices, use patterns, and/or statisticssummarizing sensor readings can be transmitted. The results orstatistics can be provided via the Internet 162. In this manner,processing engines 206 can be configured and programmed to derive avariety of useful information from the operational data obtained fromthe smart home. A single server can include one or more engines.

The derived data can be highly beneficial at a variety of differentgranularities for a variety of useful purposes, ranging from explicitprogrammed control of the devices on a per-home, per-neighborhood, orper-region basis (for example, demand-response programs for electricalutilities), to the generation of inferential abstractions that canassist on a per-home basis (for example, an inference can be drawn thatthe homeowner has left for vacation and so security detection equipmentcan be put on heightened sensitivity), to the generation of statisticsand associated inferential abstractions that can be used for governmentor charitable purposes. For example, processing engines 206 can generatestatistics about device usage across a population of devices and sendthe statistics to device users, service providers or other entities(e.g., that have requested or may have provided monetary compensationfor the statistics). As specific illustrations, statistics can betransmitted to charities 222, governmental entities 224 (e.g., the Foodand Drug Administration or the Environmental Protection Agency),academic institutions 226 (e.g., university researchers), businesses 228(e.g., providing device warranties or service to related equipment), orutility companies 230. These entities can use the data to form programsto reduce energy usage, to preemptively service faulty equipment, toprepare for high service demands, to track past service performance,etc., or to perform any of a variety of beneficial functions or tasksnow known or hereinafter developed.

FIG. 3 illustrates an abstracted functional view of the extensibledevices and services platform of FIG. 2, with particular reference tothe processing engine 206 as well as the devices of the smart home. Eventhough the devices situated in the smart home will have an endlessvariety of different individual capabilities and limitations, they canall be thought of as sharing common characteristics in that each of themis a data consumer 302 (DC), a data source 304 (DS), a services consumer306 (SC), and a services source 308 (SS). Advantageously, in addition toproviding the essential control information needed for the devices toachieve their local and immediate objectives, the extensible devices andservices platform can also be configured to harness the large amount ofdata that is flowing out of these devices. In addition to enhancing oroptimizing the actual operation of the devices themselves with respectto their immediate functions, the extensible devices and servicesplatform can also be directed to “repurposing” that data in a variety ofautomated, extensible, flexible, and/or scalable ways to achieve avariety of useful objectives. These objectives may be predefined oradaptively identified based on, e.g., usage patterns, device efficiency,and/or user input (e.g., requesting specific functionality).

For example, FIG. 3 shows processing engine 206 as including a number ofparadigms 310. Processing engine 206 can include a managed servicesparadigm 310 a that monitors and manages primary or secondary devicefunctions. The device functions can include ensuring proper operation ofa device given user inputs, estimating that (e.g., and responding to) anintruder is or is attempting to be in a dwelling, detecting a failure ofequipment coupled to the device (e.g., a light bulb having burned out),implementing or otherwise responding to energy demand response events,or alerting a user of a current or predicted future event orcharacteristic. Processing engine 206 can further include anadvertising/communication paradigm 310 b that estimates characteristics(e.g., demographic information), desires and/or products of interest ofa user based on device usage. Services, promotions, products or upgradescan then be offered or automatically provided to the user. Processingengine 206 can further include a social paradigm 310 c that usesinformation from a social network, provides information to a socialnetwork (for example, based on device usage), processes data associatedwith user and/or device interactions with the social network platform.For example, a user's status as reported to their trusted contacts onthe social network could be updated to indicate when they are home basedon light detection, security system inactivation or device usagedetectors. As another example, a user may be able to share device-usagestatistics with other users. Processing engine 206 can include achallenges/rules/compliance/rewards paradigm 310 d that informs a userof challenges, rules, compliance regulations and/or rewards and/or thatuses operation data to determine whether a challenge has been met, arule or regulation has been complied with and/or a reward has beenearned. The challenges, rules or regulations can relate to efforts toconserve energy, to live safely (e.g., reducing exposure to toxins orcarcinogens), to conserve money and/or equipment life, to improvehealth, etc.

Processing engine can integrate or otherwise utilize extrinsicinformation 316 from extrinsic sources to improve the functioning of oneor more processing paradigms. Extrinsic information 316 can be used tointerpret operational data received from a device, to determine acharacteristic of the environment near the device (e.g., outside astructure that the device is enclosed in), to determine services orproducts available to the user, to identify a social network orsocial-network information, to determine contact information of entities(e.g., public-service entities such as an emergency-response team, thepolice or a hospital) near the device, etc., to identify statistical orenvironmental conditions, trends or other information associated with ahome or neighborhood, and so forth.

An extraordinary range and variety of benefits can be brought about by,and fit within the scope of, the described extensible devices andservices platform, ranging from the ordinary to the profound. Thus, inone “ordinary” example, each bedroom of the smart home can be providedwith a smoke/fire/CO alarm that includes an occupancy sensor, whereinthe occupancy sensor is also capable of inferring (e.g., by virtue ofmotion detection, facial recognition, audible sound patterns, etc.)whether the occupant is asleep or awake. If a serious fire event issensed, the remote security/monitoring service or fire department isadvised of how many occupants there are in each bedroom, and whetherthose occupants are still asleep (or immobile) or whether they haveproperly evacuated the bedroom. While this is, of course, a veryadvantageous capability accommodated by the described extensible devicesand services platform, there can be substantially more “profound”examples that can truly illustrate the potential of a larger“intelligence” that can be made available. By way of perhaps a more“profound” example, the same data bedroom occupancy data that is beingused for fire safety can also be “repurposed” by the processing engine206 in the context of a social paradigm of neighborhood childdevelopment and education. Thus, for example, the same bedroom occupancyand motion data discussed in the “ordinary” example can be collected andmade available for processing (properly anonymized) in which the sleeppatterns of schoolchildren in a particular ZIP code can be identifiedand tracked. Localized variations in the sleeping patterns of theschoolchildren may be identified and correlated, for example, todifferent nutrition programs in local schools.

FIG. 4 is a schematic diagram of an HVAC system, according to someembodiments. HVAC system 103 provides heating, cooling, ventilation,and/or air handling for an enclosure, such as structure 150 depicted inFIG. 1. System 103 depicts a forced air type heating and cooling system,although according to other embodiments, other types of HVAC systemscould be used such as radiant heat based systems, heat-pump basedsystems, and others.

For carrying out the heating function, heating coils or elements 442within air handler 440 provide a source of heat using electricity or gasvia line 436. Cool air is drawn from the enclosure via return air duct446 through filter 470, using fan 438 and is heated through heatingcoils or elements 442. The heated air flows back into the enclosure atone or more locations via supply air duct system 452 and supply airregisters such as register 450. In cooling, an outside compressor 430passes a refrigerant gas through a set of heat exchanger coils and thenthrough an expansion valve. The gas then goes through line 432 to thecooling coils or evaporator coils 434 in the air handler 440 where itexpands, cools and cools the air being circulated via fan 438. Ahumidifier 454 may optionally be included in various embodiments thatreturns moisture to the air before it passes through duct system 452.Although not shown in FIG. 4, alternate embodiments of HVAC system 103may have other functionality such as venting air to and from theoutside, one or more dampers to control airflow within the duct system452 and an emergency heating unit. Overall operation of HVAC system 103is selectively actuated by control electronics 412 communicating withthermostat 102 over control wires 448.

The Smart-Home Thermostat

FIGS. 5A-5D illustrate a thermostat having a rounded exterior appearanceand including one or more sensors for detecting environmentalconditions, such as occupancy and/or users, temperature, ambient light,humidity, and so forth. FIG. 5A is front view, FIG. 5B is a bottomelevation, FIG. 5C is a right side elevation, and FIG. 5D is perspectiveview of thermostat 102. Unlike many prior art thermostats, thermostat102 has a simple and elegant design. Moreover, user interaction withthermostat 102 is facilitated and greatly enhanced over knownconventional thermostats. The thermostat 102 includes control circuitryand is electrically connected to an HVAC system 103, such as is shown inFIGS. 1-4. Thermostat 102 is wall mountable, is circular in shape, andhas an outer rotatable ring 512 for receiving user input. Thermostat 102has a large convex rounded front face lying inside the outer rotatablering 512. According to some embodiments, thermostat 102 is approximately84 mm in diameter and protrudes from the wall, when wall mounted, by 30mm. The outer rotatable ring 512 allows the user to make adjustments,such as selecting a new setpoint temperature. For example, by rotatingthe outer ring 512 clockwise, the real-time (i.e. currently active)setpoint temperature can be increased, and by rotating the outer ring512 counter-clockwise, the real-time setpoint temperature can bedecreased.

The front face of the thermostat 102 comprises a cover 514 thataccording to some embodiments is polycarbonate, and a lens 510 having anouter shape that matches the contours of the curved outer front face ofthe thermostat 102. According to some embodiments, Fresnel lens elementsmay are formed on the interior surface of the lens 510 such that theyare not obviously visible by viewing the exterior of the thermostat 102.Behind the lens 510 is a passive infrared (PIR) sensor 550 for detectingoccupancy, a temperature sensor that is thermally coupled to the lens510, and a multi-channel thermopile for detecting occupancy, userapproaches, and motion signatures. The Fresnel lens elements of the lens510 are made from a high-density polyethylene (HDPE) that has aninfrared transmission range appropriate for sensitivity to human bodies.The lens 510 may also include thin sections that allow a near-fieldproximity sensor 552, such as a multi-channel thermopile, and atemperature sensor to “see-through” the lens 510 with minimalinterference from the polyethylene. As shown in FIGS. 5A-5D, the frontedge of the outer rotatable ring 512, cover 514, and lens 510 are shapedsuch that they together form an integrated convex rounded front facethat has a common outward arc or spherical shape arcing outward.

Although being formed from a single lens-like piece of material such aspolycarbonate, the cover 514 has two different regions or portionsincluding an outer portion 514 o and a central portion 514 i. Accordingto some embodiments, the cover 514 is darkened around the outer portion514 o, but leaves the central portion 514 i visibly clear so as tofacilitate viewing of an electronic display 516 disposed underneath.According to some embodiments, the cover 514 acts as a lens that tendsto magnify the information being displayed in electronic display 516 tousers. According to some embodiments the central electronic display 516is a dot-matrix layout (i.e. individually addressable) such thatarbitrary shapes can be generated. According to some embodiments,electronic display 516 is a backlit, color liquid crystal display (LCD).An example of information displayed on the electronic display 516 isillustrated in FIG. 5A, and includes central numerals 520 that arerepresentative of a current setpoint temperature. The thermostat 102 maybe constructed such that the electronic display 516 is at a fixedorientation and does not rotate with the outer rotatable ring 512. Forsome embodiments, the cover 514 and lens 510 also remain at a fixedorientation and do not rotate with the outer ring 512. In alternativeembodiments, the cover 514 and/or the lens 510 can rotate with the outerrotatable ring 512. According to one embodiment in which the diameter ofthe thermostat 102 is about 84 mm, the diameter of the electronicdisplay 516 is about 54 mm. According to some embodiments the curvedshape of the front surface of thermostat 102, which is made up of thecover 514, the lens 510 and the front facing portion of the ring 512, isspherical, and matches a sphere having a radius of between 100 mm and180 mm. According to some embodiments, the radius of the spherical shapeof the thermostat front is about 156 mm.

Motion sensing with PIR sensor 550 as well as other techniques can beused in the detection and/or prediction of occupancy. According to someembodiments, occupancy information is used in generating an effectiveand efficient scheduled program. A second near-field proximity sensor552 is also provided to detect an approaching user. The near-fieldproximity sensor 552 can be used to detect proximity in the range of upto 10-15 feet. the PIR sensor 550 and/or the near-field proximity sensor552 can detect user presence such that the thermostat 102 can initiate“waking up” and/or providing adaptive screen displays that are based onuser motion/position when the user is approaching the thermostat andprior to the user touching the thermostat. Such use of proximity sensingis useful for enhancing the user experience by being “ready” forinteraction as soon as, or very soon after the user is ready to interactwith the thermostat. Further, the wake-up-on-proximity functionalityalso allows for energy savings within the thermostat by “sleeping” whenno user interaction is taking place our about to take place.

According to some embodiments, the thermostat 102 may be controlled byat least two types of user input, the first being a rotation of theouter rotatable ring 512 as shown in FIG. 5A, and the second being aninward push on head unit 540 until an audible and/or tactile “click”occurs. For such embodiments, the head unit 540 is an assembly thatincludes the outer ring 512, the cover 514, the electronic display 516,and the lens 510. When pressed inwardly by the user, the head unit 540travels inwardly by a small amount, such as 0.5 mm, against an interiorswitch (not shown), and then springably travels back out when the inwardpressure is released, providing a tactile “click” along with acorresponding audible clicking sound. Thus, for the embodiment of FIGS.5A-5D, an inward click can be achieved by direct pressing on the outerrotatable ring 512 itself, or by indirect pressing of the outerrotatable ring 512 by virtue of providing inward pressure on the cover514, the lens 510, or by various combinations thereof. For otherembodiments, the thermostat 102 can be mechanically configured such thatonly the outer ring 512 travels inwardly for the inward click input,while the cover 514 and lens 510 remain motionless.

FIG. 5B and FIG. 5C are bottom and right side elevation views of thethermostat 102. According to some embodiments, the thermostat 102includes a processing system 560, display driver 564 and a wirelesscommunications system 566. The processing system 560 is adapted to causethe display driver 564 and display 516 to display information to theuser, and to receiver user input via the outer rotatable ring 512. Theprocessing system 560, according to some embodiments, is capable ofcarrying out the governance of the operation of thermostat 102 includingvarious user interface features. The processing system 560 is furtherprogrammed and configured to carry out other operations, such asmaintaining and updating a thermodynamic model for the enclosure inwhich the HVAC system is installed. According to some embodiments, awireless communications system 566 is used to communicate with devicessuch as personal computers, other thermostats or HVAC system components,smart phones, local home wireless networks, routers, gateways, homeappliances, security systems, hazard detectors, remote thermostatmanagement servers, distributed sensors and/or sensor systems, and othercomponents it the modern smart-home environment. Such communications mayinclude peer-to-peer communications, communications through one or moreservers located on a private network, or and/or communications through acloud-based service.

According to some embodiments, the thermostat 102 includes a head unit540 and a backplate (or wall dock) 542. Head unit 540 of thermostat 102is slidably mountable onto back plate 542 and slidably detachabletherefrom. According to some embodiments the connection of the head unit540 to backplate 542 can be accomplished using magnets, bayonet, latchesand catches, tabs, and/or ribs with matching indentations, or simplyfriction on mating portions of the head unit 540 and backplate 542. Alsoshown in FIG. 5A is a rechargeable battery 522 that is recharged usingrecharging circuitry 524 that uses power from backplate that is eitherobtained via power harvesting (also referred to as power stealing and/orpower sharing) from the HVAC system control circuit(s) or from a commonwire, if available. According to some embodiments, the rechargeablebattery 522 may include a single cell lithium-ion battery, or alithium-polymer battery.

FIGS. 6A-6B illustrate exploded front and rear perspective views,respectively, of the thermostat 102 with respect to its two maincomponents, which are the head unit 540 and the backplate 542. In thedrawings shown herein, the “z” direction is outward from the wall, the“y” direction is the toe-to-head direction relative to a walk-up user,and the “x” direction is the user's left-to-right direction.

FIGS. 6C-6D illustrate exploded front and rear perspective views,respectively, of the head unit 540 with respect to its primarycomponents. Head unit 540 includes, a back cover 636, a bottom frame634, a battery assembly 632 with the rechargeable battery 522, a headunit printed circuit board (PCB) 654, the outer rotatable ring 512, thecover 514, and the lens 510. Behind the lens is the display assembly630, which will be described in relation to FIGS. 6E-6F below.Electrical components on the head unit PCB 654 can connect to electricalcomponents on the back plate 542 by virtue of a plug-type electricalconnector on the back cover 636. The head unit PCB 654 is secured tohead unit back cover 636 and display assembly 630. The outer rotatablering 512 is held between a bearing surface on the display assembly 630and bearing surfaces on the bottom frame 634. Motion of the outerrotatable ring 512 in the z direction is constrained by flat bearingsurfaces on the display assembly 630 and bottom frame 634, while motionof the ring in x and y directions are constrained at least in part bycircular rounded surfaces on the bottom frame 634. According to someembodiments, the bearing surfaces of the bottom frame 634 and/or thedisplay assembly 630 are greased and/or otherwise lubricated to bothsmooth and dampen rotational movement for the outer ring 512. The headunit printed PCB 654 may include some or all of processing system 560,display driver 564, wireless communication system 566, and batteryrecharging circuitry 524 as shown and described with respect to FIG. 5A,as well as one or more additional memory storage components. Accordingto some embodiments, circuitry and components are mounted on both sidesof head unit PCB 654. Although not shown, according to some embodiments,shielding can surround circuitry and components on both sides of thehead unit PCB 654.

Battery assembly 632 includes a rechargeable battery 522. Batteryassembly 632 also includes connecting wires 666, and a battery mountingfilm that is attached to battery 522 using a strong adhesive and/or theany rear shielding of head unit PCB 654 using a relatively weakeradhesive. According to some embodiments, the battery assembly 632 isuser-replaceable.

FIGS. 6E-6F illustrate exploded front and rear perspective views,respectively, of the head unit 540 with an exploded view of the displayassembly 630. The display assembly 630 comprises the cover 514, the lens510, an LCD module 662, a pair of RF antennas 661, a head unit top frame652, a sensor flex assembly 663, and a magnetic ring 665. The sensorflex assembly 663 connects to the head unit PCB 654 using a connector ona flexible PCB. The sensor flex assembly 663 also includes the PIRsensor 550 and the near-field proximity sensor 552. Additionally, thesensor flex assembly 663 may include a temperature sensor IC that ispositioned close to the lens 515 so as to accurately measure temperatureoutside of the thermostat 102 without being overly affected by internalheating of thermostat components. The sensor flex assembly 663 may becomprised of these three sensors, along with a flexible PCB (includingthe connector for the head unit PCB 654) and a plastic bracket to whichthe sensors and flexible PCB are mounted. The bracket ensures that thesensor flex assembly 663 is positioned and oriented consistently andcorrectly with respect to the lens 510. The lens 510 includes twosections that are thinned to approximately 0.3 mm in front of thenear-field proximity sensor 552 and the temperature sensor. The lens 510also includes a section with a Fresnel lens pattern in front of the PIRsensor 550. In some embodiments, additional temperature sensors may beplaced throughout the thermostat 102, such as a temperature sensor onthe head unit PCB 654 and a temperature sensor on the back plate PCB680.

The head unit PCB 554 includes a Hall effect sensor that senses rotationof the magnetic ring 665. The magnetic ring 665 is mounted to the insideof the outer rotatable ring 512 using an adhesive such that the outerrotatable ring 512 and the magnetic ring 665 are rotated together. Themagnetic ring 665 includes striated sections of alternating magneticpolarity that are diagonally positioned around the magnetic ring 665.The Hall effect sensor senses the alternations between magneticpolarities as the outer ring 512 is rotated. The Hall effect sensor canbe controlled by a primary processor, which is a higher poweredprocessor, without excessive power drain implications because theprimary processor will invariably be awake already when the user ismanually turning the outer rotatable ring 512 to control the userinterface. Advantageously, very fast response times can also be providedby the primary processor.

The antennas 661 are mounted to the top surface of the head unit topframe 652. The wireless communications system 566 may include Wi-Firadios of various frequencies (e.g., 2.4 GHz and 5.0 GHz), along with anIEEE 802.15.4-compliant radio unit for a local-area smart home devicenetwork that may include other thermostats, hazard detectors, securitysystem modules, and so forth. The IEEE 802.15.4 unit may use the Threadprotocol for achieving such communications. In some embodiments, thewireless communications system 566 may also include a Bluetooth lowenergy (BLE) radio for communication with user devices.

The processing system 560 may be primarily located on the head unit PCB654 and may include a primary processor and a secondary processor. Theprimary processor may be a comparatively high-powered processor, such asthe AM3703 chip, or the MCIMX6X3EVK10AB chip from Freescale™, and may beprogrammed to perform sophisticated thermostat operations, such astime-to-temperature calculations, occupancy determination algorithms,ambient temperature compensation calculations, software updates,wireless transmissions, operation of the display driver 564, andregulation of the recharging circuitry 524. The secondary processor,such as the STM32L chip from ST microelectronics, may be a comparativelylow-power processor when compared to the primary processor. Thesecondary processor may interact with the HVAC system to control aseries of FET switches that control the functioning of the HVAC system.The secondary processor may also interface with various sensors inthermostat 102, such as the temperature sensors, a humidity sensor, anambient light sensor, and/or the like. The secondary processor may alsoshare duties with the primary processor in regulating the rechargingcircuitry 522 to provide power to all of the electrical systems on boardthe thermostat 102. Generally, the primary processor will operate in a“sleep” mode until high-power processing operations (e.g., wirelesscommunications, user interface interactions, time-to-temperaturecalculations, thermal model calculations, etc.) are required, while thesecondary processor will operate in an “awake” mode more often than theprimary processor in order to monitor environmental sensors and wake theprimary processor when needed.

FIGS. 6G-6H illustrate exploded front and rear perspective views,respectively, of the back plate unit 542 with respect to its primarycomponents, according to some embodiments. Back plate unit 542 comprisesa back plate rear plate 682, a back plate PCB 680, and a back platecover 670. Visible in FIG. 6G are the HVAC wire connectors 684 thatinclude integrated mechanical wire insertion sensing circuitry, andrelatively large capacitors 686 that are used by part of the powerstealing circuitry that is mounted on the back plate PCB 680. Accordingto some embodiments, backplate 542 includes electronics and atemperature/humidity sensor in housing. Wire connectors 684 are providedto allow for connection to HVAC system wires, which pass though thelarge central circular opening 690, which is visible in each of thebackplate primary components. Also visible in each of the backplateprimary components are two mounting holes 692 and 694 for use in fixingthe backplate to the wall. Also visible in FIGS. 6G-6H are a bubblelevel 672 to allow the user to install the thermostat 102 in a levelposition without additional tools.

The back plate PCB 680 also may include approximately seven custom powerisolation ICs 685 that isolate the internal electronics of thethermostat 102 from the relatively high 24 VAC signals of the HVACsystem. The power isolation ICs 685 are custom software-resettable fusesthat both monitor transient and anomalous voltage/current signals on theHVAC power/return wires and switch off the connection to isolate thethermostat against any dangerous signals that could damage the internalelectronics. The power isolation ICs 685 receive command signals encodedin a clock square wave from the processing system 560 to open and closea pair of power FETs for each HVAC return wire in order to activate thecorresponding HVAC function (e.g., fan, air-conditioning, heat, heatpump, etc.). A complete description of the power isolation ICs 685 isgiven in the commonly assigned U.S. patent application Ser. No.14/591,804 filed on Jan. 7, 2015, which is hereby incorporated herein byreference in its entirety for all purposes.

FIG. 7 illustrates a power management and power harvesting system for asmart thermostat, according to some embodiments. FIG. 7 showsconnections to common HVAC wiring, such as a W (heat call relay wire); Y(cooling call relay wire); Y2 (second stage cooling call relay wire); Rh(heat call relay power); Rc (cooling call relay power); G (fan callrelay wire); O/B (heat pump call relay wire); AUX (auxiliary call relaywire); HUM (humidifier call relay wire); and C (common wire). Asdiscussed above, the thermostat 102 comprises a plurality of FETswitches 706 (such as the power isolation ICs 685 of FIG. 6H above) usedfor carrying out the essential thermostat operations of connecting or“shorting” one or more selected pairs of HVAC wires together accordingto the desired HVAC operation. The operation of each of the FET switches706 is controlled by the secondary processor 708 which can comprise, forexample, an STM32L 32-bit ultra-low power ARM-based microprocessoravailable from ST Microelectronics.

Thermostat 102 further comprises powering circuitry 710 that comprisescomponents contained on both the backplate 542 and head unit 540.Generally speaking, it is the purpose of powering circuitry 710 toextract electrical operating power from the HVAC wires and convert thatpower into a usable form for the many electrically-driven components ofthe thermostat 102. Thermostat 102 further comprises insertion sensingcomponents 712 configured to provide automated mechanical and electricalsensing regarding the HVAC wires that are inserted into the thermostat102. Thermostat 102 further comprises a relatively high-power primaryprocessor 732, such as an AM3703 Sitara ARM microprocessor availablefrom Texas Instruments, that provides the main general governance of theoperation of the thermostat 102. Thermostat 102 further comprisesenvironmental sensors 734/738 (e.g., temperature sensors, humiditysensors, active IR motion sensors, passive IR motion sensors,multi-channel thermopiles, ambient visible light sensors,accelerometers, ambient sound sensors, ultrasonic/infrasonic soundsensors, microwave sensors, GPS sensors, etc.), as well as othercomponents 736 (e.g., electronic display devices and circuitry, userinterface devices and circuitry, wired communications circuitry,wireless communications circuitry, etc.) that are operatively coupled tothe primary processor 732 and/or secondary processor 708 andcollectively configured to provide the functionalities described in theinstant disclosure.

The insertion sensing components 712 include a plurality of HVAC wiringconnectors 684, each containing an internal springable mechanicalassembly that, responsive to the mechanical insertion of a physical wirethereinto, will mechanically cause an opening or closing of one or morededicated electrical switches associated therewith. With respect to theHVAC wiring connectors 684 that are dedicated to the C, W, Y, Rc, and Rhterminals, those dedicated electrical switches are, in turn, networkedtogether in a manner that yields the results that are illustrated inFIG. 7 by the blocks 716 and 718. The output of block 716, which isprovided at a node 719, is dictated solely by virtue of the particularcombination of C, W, and Y connectors into which wires have beenmechanically inserted in accordance with the following rules: if a wireis inserted into the C connector, then the node 719 becomes the C noderegardless of whether there are any wires inserted into the Y or Wconnectors; if no wire is inserted into the C connector and a wire isinserted into the Y connector, then the node 719 becomes the Y noderegardless of whether there is a wire inserted into the W connector; andif no wire is inserted into either of the C or Y connectors, then thenode 719 becomes the W node. Block 718 is shown as being coupled to theinternal sensing components 712 by virtue of double lines termed“mechanical causation,” for the purpose of denoting that its operation,which is either to short the Rc and Rh nodes together or not to shortthe Rc and Rh nodes together. Whether the block 718 will short, or notshort, the Rc and Rh nodes together is dictated solely by virtue of theparticular combination of Rc and Rh connectors into which wires havebeen mechanically inserted. Block 718 will keep the Rc and Rh nodesshorted together, unless wires have been inserted into both the Rc andRh connectors, in which case the block 718 will not short the Rc and Rhnodes together because a two-HVAC-transformer system is present. Theinsertion sensing circuitry 712 is also configured to provide at leasttwo signals to the secondary processor 708, the first being a simple“open” or “short” signal that corresponds to the mechanical insertion ofa wire, and the second being a voltage or other level signal thatrepresents a sensed electrical signal at that terminal. The first andsecond electrical signals for each of the respective wiring terminalscan advantageously be used as a basis for basic “sanity checking” tohelp detect and avoid erroneous wiring conditions.

Basic operation of each of the FET switches 706 is achieved by virtue ofa respective control signal (e.g., W-CTL, Y-CTL) provided by thesecondary processor 708 that causes the corresponding FET switch 706 to“connect” or “short” its respective HVAC lead inputs for an ON controlsignal, and that causes the corresponding FET switch 706 to “disconnect”or “leave open” or “open up” its respective HVAC lead inputs for an“OFF” control signal. By virtue of the above-described operation ofblock 718, it is automatically the case that for single-transformersystems having only an “R” wire (rather than separate Rc and Rh wires aswould be present for two-transformer systems), that “R” wire can beinserted into either of the Rc or Rh terminals, and the Rh-Rc nodes willbe automatically shorted to form a single “R” node, as needed for properoperation. In contrast, for dual-transformer systems, the insertion oftwo separate wires into the respective Rc and Rh terminals will causethe Rh-Rc nodes to remain disconnected to maintain two separate Rc andRh nodes, as needed for proper operation.

Referring now to the powering circuitry 710 in FIG. 7, provided is aconfiguration that automatically adapts to the powering situationpresented to the thermostat 102 at the time of installation andthereafter. The powering circuitry 710 comprises a full-wave bridgerectifier 720, a storage and waveform-smoothing bridge output capacitor722 (which can be, for example, on the order of 30 microfarads), a buckregulator circuit system 724, a power-and-battery (PAB) regulationcircuit 728, and a rechargeable lithium-ion battery 730. In conjunctionwith other control circuitry including backplate power managementcircuitry 727, head unit power management circuitry 729, and thesecondary processor 708, the powering circuitry 710 is configured andadapted to have the characteristics and functionality describedhereinbelow.

By virtue of the configuration illustrated in FIG. 7, when there is a“C” wire presented upon installation, the powering circuitry 710operates as a relatively high-powered, rechargeable-battery-assistedAC-to-DC converting power supply. When there is not a “C” wirepresented, the powering circuitry 710 operates as a power-stealing,rechargeable-battery-assisted AC-to-DC converting power supply. Asillustrated in FIG. 7, the powering circuitry 710 generally serves toprovide the voltage Vcc MAIN that is used by the various electricalcomponents of the thermostat 102, and that in one embodiment willusually be about 3.7V˜3.95V. The general purpose of powering circuitry710 is to convert the 24 VAC presented between the input leads 719 and717 to a steady DC voltage output at the Vcc MAIN node to supply thethermostat electrical power load.

Operation of the powering circuitry 710 for the case in which the “C”wire is present is now described. When the 24 VAC input voltage betweennodes 719 and 717 is rectified by the full-wave bridge rectifier 720, aDC voltage at node 723 is present across the bridge output capacitor722, and this DC voltage is converted by the buck regulator system 724to a relatively steady voltage, such as 4.4 volts, at node 725, whichprovides an input current I_(BP) to the power-and-battery (PAB)regulation circuit 728.

The secondary processor 708 controls the operation of the poweringcircuitry 710 at least by virtue of control leads leading between thesecondary processor 708 and the PAB regulation circuit 728, which forone embodiment can include an LTC4085-4 chip available from LinearTechnologies Corporation. The LTC4085-4 is a USB power manager andLi-Ion/Polymer battery charger originally designed for portablebattery-powered applications. The PAB regulation circuit 728 providesthe ability for the secondary processor 708 to specify a maximum valueI_(BP)(max) for the input current I_(BP). The PAB regulation circuit 728is configured to keep the input current at or below I_(BP)(max), whilealso providing a steady output voltage Vcc, such as 4.0 volts, whilealso providing an output current Icc that is sufficient to satisfy thethermostat electrical power load, while also tending to the charging ofthe rechargeable battery 730 as needed when excess power is available,and while also tending to the proper discharging of the rechargeablebattery 730 as needed when additional power (beyond what can be providedat the maximum input current I_(BP)(max)) is needed to satisfy thethermostat electrical power load.

Operation of the powering circuitry 710 for the case in which the “C”wire is not present is now described. As used herein, “inactive powerstealing” refers to the power stealing that is performed during periodsin which there is no active call in place based on the lead from whichpower is being stolen. As used herein, “active power stealing” refers tothe power stealing that is performed during periods in which there is anactive call in place based on the lead from which power is being stolen.

During inactive power stealing, power is stolen from between, forexample, the “Y” wire that appears at node 719 and the Rc lead thatappears at node 717. There will be a 24 VAC HVAC transformer voltagepresent across nodes 719/717 when no cooling call is in place (i.e.,when the Y-Rc FET switch is open). For one embodiment, the maximumcurrent I_(BP)(max) is set to a relatively modest value, such as 20 mA,for the case of inactive power stealing. Assuming a voltage of about 4.4volts at node 725, this corresponds to a maximum output power from thebuck regulator system 724 of about 88 mW. This power level of 88 mW hasbeen found to not accidentally trip the HVAC system into an “on” statedue to the current following through the call relay coil. During thistime period, the PAB regulator 728 operates to discharge the battery 730during any periods of operation in which the instantaneous thermostatelectrical power load rises above 88 mW, and to recharge the battery (ifneeded) when the instantaneous thermostat electrical power load dropsbelow 88 mW. The thermostat 700 is configured such that the averagepower consumption is well below 88 mW, and indeed for some embodimentsis even below 10 mW on a long-term time average.

Operation of the powering circuitry 710 for “active power stealing” isnow described. During an active heating/cooling call, it is necessaryfor current to be flowing through the HVAC call relay coil sufficient tomaintain the HVAC call relay in a “tripped” or ON state at all timesduring the active heating/cooling call. The secondary processor 708 isconfigured by virtue of circuitry denoted “PS MOD” to turn, for example,the Y-Rc FET switch OFF for small periods of time during the activecooling call, wherein the periods of time are small enough such that thecooling call relay does not “un-trip” into an OFF state, but wherein theperiods of time are long enough to allow inrush of current into thebridge rectifier 720 to keep the bridge output capacitor 722 to areasonably acceptable operating level. For one embodiment, this isachieved in a closed-loop fashion in which the secondary processor 708monitors the voltage V_(BR) at node 723 and actuates the signal Y-CTL asnecessary to keep the bridge output capacitor 722 charged. According toone embodiment, it has been found advantageous to introduce a delayperiod, such as 60-90 seconds, following the instantiation of an activeheating/cooling cycle before instantiating the active power stealingprocess. This delay period has been found useful in allowing manyreal-world HVAC systems to reach a kind of “quiescent” operating statein which they will be much less likely to accidentally un-trip away fromthe active cooling cycle due to active power stealing operation of thethermostat 102. According to another embodiment, it has been foundfurther advantageous to introduce another delay period, such as 60-90seconds, following the termination of an active cooling cycle beforeinstantiating the inactive power stealing process. This delay period haslikewise been found useful in allowing the various HVAC systems to reacha quiescent state in which accidental tripping back into an activecooling cycle is avoided.

Sensor Flex Assembly

As described above in relation to FIG. 6A-6H, the smart thermostatincludes a sensor flex assembly 663 positioned towards the lower frontportion of the smart thermostat. The sensor flex assembly includes threedifferent sensors that are used to detect and interpret environmentalconditions in the area surrounding the thermostat at the installationlocation. While some sensors on the smart thermostat can be locatedinternally to measure internal heating, current flow through the powermanagement system, mechanical actuation of the user interface ring, andso forth, other sensors may benefit from being located as close to theoutside environment as possible. For example, sensors such as an ambienttemperature sensor, an ambient light sensor, a PIR motion detector,and/or a multi-channel thermopile may be used to detect motion,temperature, light, and occupancy within the area surrounding thethermostat. Each of the sensors may require some sort of interface withthe outside environment that surrounds the smart thermostat. The sensorflex assembly 663 provides for a mechanical/electrical solution thatproperly positions and aligns these external-facing sensors such thatthey can measure external conditions while being positioned inside thehousing of the smart thermostat.

FIGS. 8A-8B illustrate perspective views of the sensor flex assembly.FIGS. 8C-8D illustrate top and bottom views of the sensor flex assembly.FIGS. 8E-8F illustrate left and right side views of the sensor flexassembly. FIGS. 8G-8H illustrate front and back views of the sensor flexassembly. The sensor flex assembly includes at least three differentsensors packaged in three separate integrated circuits. The first sensoris a PIR sensor 802 that can detect far-field infrared signals that canbe interpreted as motion from a user. The PIR sensor 802 may beimplemented using the PYD5731 package from Excelitas™ and may have aresponsive range of up to 30 feet. The PIR sensor 802 can be mountedusing through-hole pins 816 arranged on the back of the PIR sensor 802that can be used during installation to ensure that the PIR sensor 802is oriented in the correct position.

The sensor flex assembly may also include a temperature sensor 806 thatis used primarily to detect an ambient temperature in the environmentsurrounding the smart thermostat. The temperature sensor 806 may beimplemented using a TMP112 serial temperature sensor from TexasInstruments™, or another temperature sensor that includes an ambientlight sensor (ALS) in the same package. In some embodiments, thetemperature sensor 806 may receive a temperature reading through one ofthe metal pins of the package of the temperature sensor 806. In someembodiments, the temperature sensor 806 may also include an integratedhumidity sensor. In addition to locating the temperature sensor 806 asclose to the thermostat housing as possible, it may also be desirable tothermally isolate the temperature sensor 806 as much as possible fromthe rest of the internal circuitry, including the other sensors andsystems on the sensor flex assembly.

The sensor flex assembly may also include a multi-channel thermopile804. The multi-channel thermopile 804 may function as a near-fieldproximity sensor by detecting infrared energy emitted from occupants asthey move within the different responsive ranges of the multiplechannels. In some embodiments, the multi-channel thermopile 804 may beimplemented using the AsahiKASEI® AK9750 4-channel IR Sensor IC, whichuses four quantum IR sensors. The AK9750 also provides outputs from ananalog-to-digital converter using 16-bit outputs. These four channelsmay be arranged such that an up, down, left, and right channel areprovided. Using the multi-channel thermopile 804 to detect and interpretuser motions and commands will be described in greater detail later inthis disclosure.

Each of the three sensor packages may have different placement andorientation requirements in order to maximize their efficiency indetecting the external thermostat conditions. For example, thetemperature sensor 806 may need to be located as close to the housing ofthe thermostat as possible such that the temperature sensor 806 can becoupled to the external environment without being unduly influenced bythe internal heating effects of the smart thermostat. Similarly, themulti-channel thermopile 804 may benefit from being located andpositioned such that the IR detectors have a wide field of view of thesurrounding environment with as little interference from the housing ofthe thermostat as possible. The PIR sensor 802 may require apredetermined focal length from an IR-energy-directing element, such asa Fresnel lens. The PIR sensor 802 may also require a specific placementand orientation such that it is properly aligned with the Fresnel lens.Despite these different requirements, certain manufacturing andoperational efficiencies can be achieved by packaging these threesensors together on the sensor flex assembly. Instead of having todesign and place three separate circuit boards at different locationsand distances from the front of the thermostat, these three sensors canbe assembled and installed together in a single convenient package. Formanufacturing purposes, the sensor flex assembly can be manufactured anddelivered to the thermostat manufacturer as a complete package. Thesensor flex assembly also allows a single connector to facilitatecommunications between the primary processor and each of the threesensors. Without the sensor flex assembly, three different circuitboards would be required with three different connectors, which wouldnecessarily require a more complex installation and use valuableinternal space to route these connections. Providing the sensor flexassembly also makes rework/replacement relatively easy.

In addition to these benefits provided during the manufacturing of thesensor flex assembly, the sensor flex assembly can also makeinstallation easier by guaranteeing that the sensors are properlyaligned. The sensor flex assembly may include a plastic bracket 820 thatcan ensure that the sensors are located and oriented the same across allmanufactured units. When installing the sensor flex assembly as acomplete piece, the installer can use alignment holes 812, 814 that arematched to pins on the thermostat assembly. Once the sensor flexassembly is properly aligned through the alignment holes 812, 814, clips810 on each side of the sensor flex assembly can lock the sensor flexassembly in place. This process rigidly fixes the sensor flex assemblyinto the thermostat and guarantees a consistent positioning alignment ofthe sensors. A multi-function lens can then be attached in front of thesensor flex assembly, which will guarantee that the sensors are alwaysthe desired distance from the lens. The multi-function lens will bedescribed in greater detail below.

In order to eliminate the problems associated with three separatecircuit boards for each of the three sensor ICs, a flexible circuitboard 822 can be used. The flexible circuit board 822 is comprised of aleft wing, to which the multi-channel thermopile 802 can be soldered, aright-wing, to which the temperature sensor 806 can be soldered, acenter portion through which the through-hole pins 816 of the PIR sensor802 can be inserted, and a top wing that includes a connector 808 thatcan be connected to the main head unit circuit board of the smartthermostat. The left wing and the right wing of the flexible circuitboard 822 can be secured to the top of the bracket 820 using adhesives.The center portion of the flexible circuit board 822 can pass behind thebracket 820 and be secured to the center portion of the bracket bysoldering the through-hole pins 816 of the PIR sensor 802. By passingthe center portion of the flexible circuit board 822 behind the bracket820, the bracket 820 acts as a spacer between the PIR sensor 802 and thecenter portion of the flexible circuit board 822. When the through-holepins 816 of the PIR sensor 802 are soldered to the flexible circuitboard 822, solder can possibly wick through the flexible circuit board822 and short the through-hole pins 816 to the body of the PIR sensor802. This can result in shorting the power pin to the ground pin of thePIR sensor 822. The spacing provided by the bracket 820 prevents thisshort from occurring during manufacturing and/or installation.

Some embodiments may include a section of conductive tape 818 that wrapsaround the body of the PIR sensor 802 and extends around the back of thebracket 820. For example, copper tape may be used as the conductive tape818. The conductive tape 818 can serve a number of purposes. In someembodiments, the conductive tape 818 can act as a Faraday cage,shielding the PIR sensor 802 from interference from RF energy. Theconductive body of the PIR sensor 802 can, in some cases, inadvertentlycouple RF transmissions into either the sensor or the sensor pins. Thiscan generate an anomalous sensor output when RF transmissions areoccurring. As described above, the smart thermostat may include a numberof different RF systems, such as a Wi-Fi system (2.4 GHz, 5 GHz), aZigBee-style radio chip for a local sensor network, a Bluetooth lowenergy chip to communicate with external devices and/or sensors, and soforth. Each of these chips may generate RF emissions that can beinadvertently coupled to the PIR sensor 802. The conductive tape 818serves in part to shield the PIR sensor 802 from such interference.Additionally, the conductive tape 818 can tie the conductive body of thePIR sensor 802 to a ground plane on the back side of the flexiblecircuit board 822.

The orientation of the bracket can guarantee that each of the sensors isproperly oriented in relation to the lens on the front of the smartthermostat. The left wing of the bracket 820 and the center portion ofthe bracket 820 can be oriented at an angle that is approximatelyparallel to an installation surface such that the multi-channelthermopile 804 and the PIR sensor 802 are oriented such that theirfields-of-view emanate perpendicularly away from the plane of theinstallation surface (e.g., they are directed outwards from a wall intoa room). In contrast, the right-wing of the racket 820 is oriented at anangle of between 60° and 80° from the plane of the installation surface.This orientation effectively turns the temperature sensor 806 such thatthe metal pin/lead of the IC package that receives the externaltemperature is placed as close as possible to the external environment.Turning the temperature sensor 806 also serves to thermally isolate themetal pin/lead that receives the external temperature from the internalenvironment of the smart thermostat.

FIG. 9 illustrates a view of the PIR sensor 802, the bracket 820, andthe flexible circuit board 822 as they are assembled to form the sensorflex assembly. Before assembly, the multi-channel thermopile 804 and thetemperature sensor 806 are soldered to the flexible circuit board 822,along with a handful of other passive circuit components. The left sideof the flexible circuit board 822 is fed up through a hole 914 in thebracket 820 and secured to the top side of the bracket with adhesives910. The notch 904 in the flexible circuit board 822 is aligned with theprotrusion 902 on the bracket 820 in order to align the multi-channelthermopile 804 correctly on the bracket 820. The middle section of theflexible circuit board 822 passes beneath the bracket 820. Thethrough-hole pins 816 of the PIR sensor 802 pass through the bracket 820and the back of the flexible circuit board 822. When the through-holepins 816 are soldered to the flexible circuit board 822, this jointholds the flexible circuit board 822, the bracket 820, and the PIRsensor 802 together. Finally, the right side of the flexible circuitboard 822 passes through a hole 916 in the bracket and is secured to thebracket using an adhesive 912. The portion of the flexible circuit board822 with the connector 808 is allowed to hang freely such that it can beconnected to the main head unit circuit board of the thermostat. Notethat the alignment holes 814, 812 pass through flexible circuit board822 and the bracket 820 in order to avoid stack up errors that wouldotherwise be aggregated when the separate pieces of the sensor flexassembly were assembled and inserted into the thermostat.

FIGS. 10A-10B illustrate conductor patterns on the flexible circuitboard 822 to isolate the temperature sensor 806 from internal heatingeffects. Modern smart thermostats, such as the smart thermostatdescribed herein, may include a number of heat-generating componentsthat, when active, will generate an excessive amount of heat internal tothe thermostat. This internal heat generation can distort measurementsmade by temperature sensors that are located within the housing of thethermostat. In order to minimize the effects of internal heating, thetemperature sensor 806 can be located on the flexible circuit board 822in a manner that minimizes thermal conduction of heat from the body ofthe thermostat into the temperature sensor 802.

The flexible circuit board 822 may include layers that are constructedfrom polymer, nylon, plastic, and/or any other material that act as athermal isolator. Thus, the flexible circuit board itself will generallynot conduct a great deal of heat unless there are copper traces thatwould allow for heat conduction. In order to isolate the temperaturesensor 806, only a minimal amount of copper may be used on the areasurrounding the temperature sensor 806. As illustrated by FIGS. 10A-10B,ground and/or power planes on the flexible circuit board 822 have beenremoved from the right side of the flexible circuit board 822 in orderto prevent these copper planes from conducting heat from the rest of thethermostat to the temperature sensor 806. Only four very small coppertraces are required to communicate power, ground, and serialcommunication to the connector 808 from the temperature sensor 806. Allother unnecessary copper has been removed. Generally, the rest of theflexible circuit board 822 will include signals that are sandwichedbetween two ground planes in order to shield those signals from the RFinterference described above.

FIGS. 10C-10D illustrate the passive component layout on the flexiblecircuit board 822 to further isolate the temperature sensor 806 frominternal heating effects. Passive components 1002, 1004, 1006 can beused to filter out noise from the RF interference described above.Component values can be chosen specifically to cause the PIR sensor 802to “float”, or appear as a disconnected high impedance at the twospecific RF frequencies likely to be encountered (2.4 GHz and 5.0 GHz).Components must be selected such that they are tuned to this widefrequency range. For example, in one embodiment, three inductors areused to in conjunction with the PIR sensor 802, and two bypasscapacitors are used near the connector 808.

FIGS. 11A-11B illustrates various views of a multifunction lens element.This lens may correspond to the lens 510 in FIGS. 5A-5D. The lens can befabricated from a single piece of high-density polyethylene (HDPE). Thismaterial is transparent to the wavelengths of the multi-channelthermopile 804 and the PIR sensor 802. Because the lens is fabricatedfrom a single piece of HDPE, several lens elements do not have to bealigned individually with the corresponding sensors on the sensor flexassembly. Instead, the entire lens can be snapped into place on the bodyof the thermostat and the different sections of the lens can beguaranteed to be properly aligned with their corresponding sensors onthe sensor flex assembly.

A multi-channel thermopile lens area 1102 can be fabricated into thelens at the area directly in front of the multi-channel thermopile 804.The closer the multi-channel thermopile 804 can be to the lens, thesmaller the radius of the multi-channel thermopile lens area 1102 needsto be. The multi-channel thermopile 804 is used to detect the frequencyof light looking straight out from the sensor. Therefore, the thinnerthe lens, the less interference will be caused by the lens, and the moreaccurate and/or sensitive the multi-channel thermopile 804 can be.Similarly, a temperature sensor lens area 1106 can be fabricated in thelens at the area directly in front of the temperature sensor 806. Boththe temperature sensor 806 and the multi-channel thermopile 804 benefitfrom the lens being as thin as possible in front of the sensors.Therefore, it may be beneficial for the multi-channel thermopile 804 andthe temperature sensor 806 to be precisely positioned in relation totheir corresponding lens areas 1102, 1106.

The center of the lens includes a Fresnel lens 1104 that is positionedin front of the PIR sensor 802 and designed to direct infrared energythat is incident on the lens onto the detectors of the PIR sensor 802.There are two sensor regions on the PIR sensor 802, one on the left, andthe other on the right. The Fresnel lens 1104 includes six differentbands. Three of the six bands direct IR energy onto the left region ofthe PIR sensor 802, and the other three bands direct IR energy onto theright half of the PIR sensor 802.

The ridges for the Fresnel lens 1104 and the radius cutout lens areas1102, 1106 can be integrally formed into the lens during manufacturing.In one embodiment, the entire lens can be injection molded with the lenspatterns inserted into the injection mold. To install the lens, holes1112 in the bottom of the lens can fit into clips on the body of thethermostat, and the tabs 1108 can be inserted into correspondingrecesses in the body of the thermostat. The lens will generally beconstructed from a flexible material, so the tabs 1108 can be insertedfirst, and the holes 1112 can then be clicked into place. Because thisonly allows the lens to be installed in a single correct position, itguarantees that the corresponding lens areas 1102, 1106 and Fresnel lens1104 will be properly aligned with their corresponding sensors.

FIG. 11C illustrates how the lens can be installed relative to thesensor flex assembly, according to some embodiments. Note that FIG. 11Cis not drawn to scale, but is instead intended to illustrate sensoralignment rather than absolute dimensions. Lens areas 1102, 1106 infront of the multi-channel thermopile 804 and the temperature sensor 806may be thicknessed to approximately 0.3 mm. The rest of the lens,including the area for the Fresnel lens 1104 may be thickness toapproximately 0.7 mm. In order to further couple the temperature sensor806 to the external environment and isolate the temperature sensor 806from internal heating of the thermostat, any gap between the temperaturesensor 806 and the lens area 1102 can be filled with thermal grease,such as Fujipoly Sarcon No. SPG-30A thermal grease.

In contrast to the multi-channel thermopile 804 and the temperaturesensor 806, the PIR sensor 804 requires a certain focal length betweenthe Fresnel lens 1104 and the PIR sensor 802. In some embodiments, thisfocal length will be between 6 mm and 8 mm. As illustrated by FIG. 11C,the PIR sensor 802 can be positioned approximately 6.6 mm behind theFresnel lens 1104.

FIGS. 11D-11E illustrate an assembly procedure for the lens 510, thesensor flex assembly 663 and the head unit top frame 652 as depicted inFIGS. 6A-6H above. As used herein, the term “sensor mount assembly” maybe used to refer to the sensor flex assembly 663, comprised of thebracket, the flexible circuit board, and the various sensors includingthe PIR sensor. As used herein, the term “lens assembly” may refer tothe lens 510. As used herein, the term “frame member” may be used torefer to the head unit top frame 652, as well as generically referringto any rigid or semi-rigid frame element to which the sensor mountassembly and the lens can be aligned.

Alignment features on the lens assembly 510, the sensor mount assembly663, and the frame member 662 can be used to assemble all three elementsand ensure that the sensors are properly aligned and spaced relative tothe lens assembly 510. The tabs 1108 on the lens assembly 510 may bereferred to as “alignment features” and/or “a second alignment feature.”Similarly, the alignment holes 812, 814 on the sensor mount assembly 663may be referred to as “alignment features” and/or “a first alignmentfeature.” The frame member 652 may include “a third alignment feature”1122, 1124 comprised of posts that fit through the alignment holes, andwhich may be said to be matably coupled with the first alignment feature812, 814. Similarly, the frame member 652 may include holes comprising“a fourth alignment feature” 1120 that can be coupled with the secondalignment feature 1108 on the lens assembly 510 to ensure accurateassembly.

Presence and Motion Detection System

Some embodiments described herein detect the presence of a user in closeproximity to a smart-home device and change the operation of thesmart-home device accordingly. For example, a smart thermostat mayinclude an advanced user interface that includes scrollable menus,graphical scheduling, setpoint temperature interfaces, animations, andso forth. These advanced operations performed by the user interface areoften very power intensive, which can place a strain on the powermanagement system of the smart thermostat when operated too frequently.Therefore, the smart thermostat may utilize proximity sensors and otherpresence-detecting inputs to determine when a user is approaching thethermostat with the intent to interact with the user interface. Thisallows the smart thermostat to judiciously conservative its resources,only activating the user interface when necessary for a positive userexperience.

The smart thermostat described above includes two different types ofproximity sensors. The first proximity sensor has a far-field rangeextending between 15 feet and 30 feet outwards from the thermostat. Inother embodiments, the first proximity sensor may include a far-fieldrange extending between 0 feet and 50 feet, depending on the particulartype of hardware sensor used. A second proximity sensor has a near-fieldrange that that may only extend 5 feet to 10 feet outwards from thethermostat. The far-field proximity sensor can be used to generallydetect the presence of a user within an enclosure, such as a home. Whena presence is detected in the home, the thermostat may continue tooperate in a normal mode, controlling the HVAC system as programmedaccording to a setpoint schedule. However, when no presence is detectedin the home, the thermostat may enter into an “auto-away” mode, wherethe setpoint temperature is raised/lowered in order to conserve energywhen the home is unoccupied. The far-field proximity sensor is usefulfor this operation because it can generally detect users that are withinthe field of view of thermostat. However, the far-field proximity sensorand proximity sensors in general may have other applications in thesmart thermostat beside simply being used for the “auto-away” feature.

The second proximity sensor has a near-field range that can also be usedto detect user presence, and can also be useful in detecting usersapproaching the thermostat in order to interact with the thermostat.Turning the user interface on can provide a welcoming user experienceand allows users to see the current temperature, the setpointtemperature, and a current HVAC function without needing to touch theuser interface. By detecting a user approach, the thermostat can balancea delicate power-management trade-off, deactivating the user interfacewhen users are not intending to interact with the thermostat, andactivating user interface upon user approach.

In some embodiments, user approach is detected when the user first comeswithin range of the far-field proximity sensor. If the user then movedinto the range of the near-field proximity sensor, the user interfacewould activate. This method for detecting a user approach is describedfully in the commonly-assigned U.S. Pat. No. 8,560,128, which isincorporated herein by reference.

In the embodiments described herein, a more advanced second proximitysensor is presented. Specifically, a multi-channel IR thermopile is usedto not only detect a user presence within the near-field range, but alsoto characterize the motion of the user. For example, a proximity sensorwith a left channel, a center channel, and a right channel maydistinguish between a user moving from left to right walking past thethermostat, a user moving right to left walking past the thermostat, anda user approaching the thermostat from the right in order to interactwith the thermostat. Responses from the various channels of thenear-field proximity sensor can be used to identify these types ofmovement patterns. These sensed patterns can be compared to knownpatterns that indicate that the user is approaching the thermostat inorder to interact with the thermostat. Using this information,thermostat systems, such as the user interface, can be more judiciouslyactivated based on user movements.

Once a user has approached the thermostat in order to interact with theuser interface, the near-field proximity sensor can perform additionalfunctions. A user can use hand gestures, such as waving their hands fromleft to right or up and down in order to provide commands to the userinterface without touching the thermostat. For example, waving from leftto right can activate user menus or scroll back and forth between menuoptions. Moving the hand of the circular motion (which may sequentiallyactivate a left channel, a down channel, a right channel, an up channel,and so forth) may be used to indicate a user command similar to therotation of the metal ring around the perimeter of the thermostat. Othercommand types and uses of the near-field proximity sensor to provideinformation to the thermostat based on user movements will be describedin greater detail below.

FIG. 12 illustrates a near-field proximity sensor range 1202 and afar-field proximity sensor range 1210, according to some embodiments.User 1212 is outside of the far-field proximity sensor range 1210.Therefore, the far-field proximity sensor on the smart-home device 1204would not generate a response, and the smart-home device 1204 would not“see” user 1212. Because user 1212 is outside of the far-field proximitysensor range 1210, the smart-home device 1204 may eventually enter intoan auto-away mode unless the user 1212 moves closer to the smart-homedevice 1204.

User 1208 is inside the far-field proximity sensor range 1210, butoutside of the near-field proximity sensor range 1202. At this stage,the smart-home device 1204 will “see” user 1208, and would know that theenclosure is occupied. This should prevent the smart-home device 1204from entering into an auto-away mode. While the user 1208 is still farenough away from the smart-home device 1204 that the user interface willnot be activated, the smart-home device 1204 can begin watching fordifferent channels of the near-field proximity sensor to generate aresponse above a predetermined threshold. In this sense, a response fromthe far-field proximity sensor can enable the processing system of thesmart-home device 1204 to begin acting on responses from the near-fieldproximity sensor. This can serve as a guard band in some embodimentsagainst false positives by requiring that a user progress through thefar-field proximity sensor range 1210 and then the near-field proximitysensor range 1202 before taking action such as activating the userinterface.

In contrast, user 1206 has entered into the near-field proximity sensorrange 1202. In some embodiments, surpassing a single thresholdindicating that the user has approached the smart-home device 1204 maybe enough to take an action such as activating the user interface. Inother embodiments, the type of motion, or the way that the user 1206approaches the smart-home device 1204 can be compared to predeterminedmovements signatures to determine whether the user 1206 is approachingthe smart-home device 1204 in order to interact with the user interface,or if the user 1206 is merely walking past the smart-home device 1204.Some users may be annoyed when the user interface is activated as theywalk by the smart-home device 1204 when they did not intend to interactwith the smart-home device 1204. Needless activation may be seen as awaste of energy or a distraction. By comparing the current motionsignature to predetermined movements signatures, a determination may bemade by the smart-home device 1204 regarding the intention of the user1206.

As used herein, the term “motion signature” may be used to describe asequence of directional indications that correspond to responsesgenerated by different channels of the near-field proximity sensor. Forexample, a motion signature may be as simple as “left, center, right” asa user moves through the respective responses zones of the near-fieldproximity sensor. In a four-channel proximity sensor, the “center”response may correspond to a response on the down channel, a response onthe up channel, and/or a combination of responses on the up and downchannels. In another example, a motion signature may include indicationsof when a user enters and/or leaves an area covered by a channel of thesensor. For example, when entering the area covered by the left channel,the motion signature may include an indication of an “arrival:left.”When the user leaves the area covered by the left channel, the motionsignature may include an indication of a “departure:left.”Arrival/departure indications for one or more zones may be combined toform the total motion signature. Motion signature examples will bedescribed in greater detail below.

FIG. 13 illustrates a diagram of movements perpendicular to the plane ofthe smart-home device 1320, according to some embodiments. Range 1318indicates the range of the far-field proximity sensor. The range of thenear-field proximity sensor may begin at range 1310, and begin togenerate responses between range 1310 and range 1316. At range 1316, auser moving towards the smart-home device 1320 is expected to generate aresponse. Beyond range 1310, a user moving towards the smart-home device1320 is not expected to generate a response. Between range 1310 andrange 1316 a user moving towards the smart-home device 1320 will beginto generate a response. Range 1314 represents a threshold value when aresponse is sufficient to be considered an indication of motion.

In one example, user 1302 moves in a straight path 1306 towards a wallon which the smart-home device 1320 is mounted, but not directly towardsthe smart-home device 1320. When the user 1302 crosses the threshold ofrange 1314 at location 1318, the near-field proximity sensor of thesmart-home device 1320 should generate a response on one or more of thechannels. Depending on how the channels are arranged, user 1302 shouldgenerate a response on the left channel, and may also generate aresponse on the up/down channel.

In another example, user 1304 moves in a straight path 1308 directlytowards the smart-home device 1302 and perpendicular to the plane of thesmart-home device 1302. When the user 1304 crosses range 1314 atlocation 1312, one or more of the channels of the near-field proximitysensor should generate a response. In this case, it is very likely thatthe up/down channel of the near-field proximity sensor will generate astrong response. It is also possible that the left channel and/or theright channel may also generate weaker responses.

Sample paths 1306 and 1308 such as those described above can be used astraining data to define the threshold level for range 1314. An optimalthreshold will usually generate a positive response for path 1308, whilepath 1306 should be right on the edge of the threshold.

FIG. 14 illustrates sample horizontal paths that may be detected by thesmart-home device 1420 using a threshold 1414, according to someembodiments. Here, a threshold can be selected such that path 1404 thatjust intersects with range 1416 of the near-field proximity sensor willgenerate a positive response, while path 1402 that just intersects withrange 1410 will not generate a positive response. FIG. 14 alsoillustrates how and arrival and departure threshold value can be set foreach zone. For the center (up/down) channel, 1404 should generate anarrival response at location 1420 while generating a departure responseat location 1418. In one particular embodiment, test paths such as theseyielded arrival/departure thresholds as listed in table 1 below.

TABLE 1 Threshold Values Channel Value Up/Down Arrival Threshold 127Left/Right Arrival Threshold 129 Up/Down Departure Threshold −55Left/Right Departure Threshold −89The values in table 1 correspond to the AsahiKASEI® AK9750 4-channel IRSensor IC, which uses four quantum IR sensors. The AK9750 also providesoutputs from an analog-to-digital converter using 16-bit outputs. Someembodiments, different thresholds may be used for the up channel thanfor the down channel, instead of using the same threshold as illustratedin Table 1.

FIG. 15 illustrates an example of a diagonal path 1502 towards thesmart-home device 1520, according to some embodiments. It is likely thatthe diagonal path 1502 will generate a response in the right channel aswell as the center (up/down) channel, crossing a threshold at location1520. In some embodiments that include a multi-channel proximity sensor,the multi-channel capability can be disregarded and the multi-channelproximity sensor can be used as a single-channel proximity sensor bysimply adding or averaging the responses of the different channelstogether. In the example of FIG. 15, the response in the left channeland the center channel can be added together to generate a singlecomposite response that indicates the user is within the threshold rangeof the near-field proximity sensor.

FIG. 16 illustrates the four-channel viewing areas of a near-fieldproximity sensor 1600, according to some embodiments. The AK9750includes an IR sensor array 1610 arranged in left, right, up, and downfacing orientations on the top of the IC package. As described above,the near-field proximity sensor 1600 is mounted to the sensor flexassembly of the smart thermostat and positioned behind a multi-functionlens that provides a Fresnel lens section for the far-field PIRproximity sensor and a thin lens section for the near-field proximitysensor 1600. The IR sensor array 1610 is positioned on the front of theIC package and oriented on the package facing towards the center. Forexample, the downward facing sensor is positioned at the top of the IRsensor array 1610. The downward facing sensor is oriented such that itis angled slightly towards the bottom of the IC package. Similarly, theleft facing sensor is positioned at the right side of the IR sensorarray 1610 and oriented such that it is angled slightly towards the leftside of the IC package. The IR sensor arrangement on the IR sensor array1610 generates four overlapping fields of view 1602, 1604, 1606, 1608.As can be seen from FIG. 16, a user approaching from the right willinitially trigger a response from the right channel, and then generatesimultaneous responses from the up channel and the down channel.

In some embodiments, it is not particularly useful to detect whether auser approaches the smart-home device from below the device or above thedevice. Instead, the responses of the up channel and the down channelcan be combined to generate a center channel. When combining the upchannel and the down channel, the down channel can be discounted using amultiplier in order to ignore responses from small children and pets. Itis unlikely that a small child is approaching the thermostat with theintent to interact with the thermostat, and activating a user interfacewhen a pet approaches is simply a waste of energy. In one embodiment, aresponse generated on the down channel can be multiplied by 0.3 beforebeing combined with the response generated from the up channel. Otherembodiments may use multipliers in the range of 0.1 to 0.7.

FIG. 17 illustrates a characteristic response of a digital filterdesigned to filter the output response of the near-field proximitysensor before being processed by the microprocessors of the processingsystem (e.g., primary processor). There is a DC component in samplesreceived from each IR channel of the near-field proximity sensor. The DCcompliment reflects the overall IR brightness of the field of viewrather than motion within the field of view. The high-frequencycomponents of received samples are dominated by thermal and/orelectrical noise, therefore, the received time series of samples fromeach channel should be filtered using a bandpass filter. For example,the following filter equation may be used.y[n]=x[n]−x[n−2]+c ₁ y[n−1]−c ₂ y[n−2]  (1)

In equation (1), x[n] indicates a raw channel sample at time n, and y[n]indicates a filtered version of the channel sample at time n. Constantvalues may be selected based on the particular type of near-fieldproximity sensor used. For example, in the case of the AK9750 describedabove, the following constant values may be used.c ₁=1.25236 and c ₂=0.2637729  (2)

The frequency response 1700 of this bandpass filter from equation (1)and equation (2) is illustrated in FIG. 17. Note that the bandpass gainis greater than one (0 dB). In some cases, the bandpass gain wasdetermined as the series combination of a first-order Butterworthhighpass filter with a normalized cutoff frequency of 1/200, along witha first-order Butterworth lowpass filter with a normalized cutofffrequency of ⅓. The scale factor on x[n]−x[n−2] has been removed to saveone multiplication in the filtering process since this factor can easilybe incorporated within the threshold values themselves.

FIG. 18 illustrates a flowchart 1800 of a method for detecting a userapproach to a smart-home device, according to some embodiments. Themethod may include detecting the motion signature with a near-fieldproximity sensor (1802). In simple embodiments, a motion signature maysimply be an indication from the near-field proximity sensor that a userhas moved within a predetermined threshold distance of the smart-homedevice. For example, a four-channel near-field proximity sensor cancombine the responses from all channels in order to generate a singleindication of whether a user is within the range of the near-fieldproximity sensor. In other embodiments, more complicated motionsignatures can be detected by the near-field proximity sensor. Asdescribed above, thresholds for each sensor can be set to determine whena user is arriving in the field of view of each channel or departingfrom the field of view of each channel. For the left and right channels,the filter response from these channels can simple be compared to thethreshold values.y _(Left) [n]≧LR_ARR_THRESH,y _(Right) [n]≧LR_ARR_THRESH  (3)

For the up/down channel, the filtered responses of these two channelscan be compared to the sum of the up channel and the discounted downchannel.y _(Up) [n]+0.3y _(Down) [n]≧UD_ARR_THRESH  (4)

Equations (3) and (4) illustrate how filtered responses from eachchannel can be used to determine whether or not a user is arriving inthat channel's field of view. Determining whether a user is departingfrom that channels field of view uses the same equations with differentthresholds (e.g., LR_DEP_THRESH and UD_DEP_THRESH). Therefore, somemotion signatures may be comprised of a single indication of whether auser is arriving or departing from a particular channel's field of view.

In some embodiments, even more complex motion signatures may bedetermined. These more complex motion signatures can be used todetermine an intended behavior of the user. For example complex motionsignatures can determine whether a user intends to approach thesmart-home device to interact with user interface, or whether the userintends to walk past the smart-home device in a hallway withoutinteracting. Complex motion signatures may be comprised of combinationsof the individual channel indications described above. For example, if auser is seen to arrive at the left channel, then to arrive at the rightchannel, then to depart the left channel, it can be inferred that theuser has passed across the front of the device from left to right.Instead of turning on the user interface, the smart-home device canremain in a sleep state. Table 2 below lists a sampling of differentcomplex motion signatures that can be constructed from channelindications.

TABLE 2 Motion Signatures Channel Indication Sequence Motion SignatureDescription ARR_L, ARR_R, DEP_L User passed across the front of thedevice from left to right ARR_L, ARR_R, DEP_R User reached device fromleft, then departed left ARR_L, ARR_R, DEP_C User reached device fromleft, then departed away from device ARR_L, R/L/C_DEP w/o Path wasoblique (only visible on the left) ARR_R ARR_C, R/L/C_DEP Direct(perpendicular) approach path

In some embodiments, a timing element may also be added to a motionsignature. Each motion signature can include a time between each channelindication received by the processing system. For example, for thesequence described above, the motion signature may be represented by:ARR_L, [1.1 sec], ARR_R, [0.6 sec], DEP_L. Adding timing information canbe very useful for determining when a user has stopped in front of thesmart-home device. For example, if the user arrives from the left, thenarrives from the right, and a certain threshold amount of time elapses(e.g., 0.5 seconds) without receiving a departure indication, it can beassumed that the user has approached the smart-home device from the leftand stopped in front of the smart-home device to interact with thesmart-home device.

The motion signature can be built gradually as responses are filteredand received from the near-field proximity sensor channels and stored ina motion signature vector that can be compared to known motionsignatures. The stored vector can be flushed if a predetermined timeinterval elapses without any movement, or when a departure is seen on athreshold number of channels.

The method may also include determining whether the received motionsignature matches any known motion signatures (1804). The smart-homedevice may receive known motion signatures in a number of differentways. First, the smart-home device may receive a library of known motionsignatures from a central management server. Certain motionsignatures—including some of those in Table 2 above—may be common tomost environments in which a smart-home device can be installed. Forexample, the motion signature indicating that a user passes in front ofthe smart-home device from left to right is a common signature that mayoccur in many installation locations. The central management server canstore a database of motion signatures that are preprogrammed based ontrials conducted in a testing environment. Alternatively oradditionally, the central management server can receive recorded motionsignatures from any of the smart-home devices connected to its network.Because the smart-home devices are distributed in homes throughout aservice area, a very large number of motion signatures can be retrievedand analyzed. The central management server can develop a histogram orother statistical analysis of the received motion signatures and selectthose motion signatures that occur most frequently over the widestdistribution of homes. These motion signatures can be assumed to becommon to many different installation environments and many differentuser types. The selected motion signatures can then be downloaded toeach of the smart-home devices connected to the network and used as atleast an initial baseline for comparison.

The smart-home device may also receive known motion signatures based onhistorical interactions in its immediate environment. As described instep (1802) above, every time responses are generated from one or morechannels of the multi-channel near-field proximity sensor, thesmart-home device will record a set of responses to generate a motionsignature. After the user leaves the area, the motion signature can thenbe stored in a historical database of motion signatures observed by theparticular smart-home device. As was the case of the central managementserver, the smart-home device can also perform a statistical analysis ofeach motion signature, developing a histogram representation using acounter for each observed motion signature that is incremented aftereach occurrence. The most common motion signatures can be added to thedatabase of known motion signatures and compared in real-time to futuremotion signatures as they are received by the smart-home device.

The smart-home device may also combine known motion signatures in itsdatabase with information received from new motion signatures. Forexample, a motion signature received from the central management servermay include timing requirements for the average person (e.g., how fastthe person moves from left to right in front of a thermostat). However,a particular smart-home device may be installed in a home with olderoccupants who move slower than the average timing requirements.Smart-home device may recognize a pattern of arrivals/departures in anexisting motion signature and adjust the timing requirements to matchthe slower/faster pace of the particular occupants in its installationlocation. Thus, the database of known motion signatures may includesignatures received from a central management server, signaturesrecorded locally by the smart-home device, and signatures that are acombination of the two as they are dynamically adjusted to match thespecific user characteristics.

Comparing the received motion signature with known motion signatures maybe processed by the processing system of the smart-home device.Alternatively or additionally, the received motion signature can be sentto the central management server for remote processing, and a responsecan then be sent to the smart-home device. Because the smart-homedevices in this disclosure are connected to the central managementserver through local wireless networks and the Internet, advanceprocessing and statistical analysis may be passed to the centralmanagement server where more processing power is generally available.This may be particularly advantageous for smart-home devices, such as ahazard detector, that use low-power processors and have limited memorystorage capabilities.

The process of matching the received motion signature to a known motionsignature may be either exact or approximate. For example, a device mayrequire an exact sequence of channel responses, while allowing timerequirements to vary within a bandpass range. This would allow users tomove faster/slower through the same sequence in front of the smart-homedevice and still generate what would be recognized as the same motionsequence. In other cases, the known motion signature should be a subsetof the received motion signature. These embodiments cover situationswhere more than one user is in range of the near-field proximity sensor.Channel responses due to a first user may be interleaved with channelresponses due to a second user. So long as a recognized sequence appearsin order in the motion signature, that sequence can be extracted andidentified in the known motion signature database. For example, so longas ARR_L, ARR_R, and DEP_R appear in the motion signature in that orderand with the correct timing, then the processing system can identify theleft-to-right motion, even if other channel responses (e.g., ARR_C) alsoappear in the motion signature due to another user.

If the received motion signature does not match a known motionsignature, then a default proximity scheme can be used to activate theuser interface of the smart-home device and/or perform other operations(1806). The default proximity scheme may simply average/add all of thechannel responses together to determine if the user has come within aspecified range of the smart-home device, and then act accordingly.However, if the received motion signature matches a known motionsignature, then more advanced operations may be carried out. Each knownmotion signature may also be stored with an indication of user intent.For example, the left-to-right motion signature described above may bestored with an indication that this motion signature rarely correspondsto a user intending to use the smart-home device, but rather correspondsto a user that simply walks by the smart-home device. This indicationmay be stored as a single bit in some embodiments, or as a statisticalpercentage in other embodiments. The statistical percentage can becompared to a threshold percentage determined if the smart-home deviceshould interpret the motion signature as an intent to use the device.The threshold can be adjusted up or down universally for all motionsignatures to make the smart-home device more or less responsive to userapproaches. Some users may prefer that the smart-home device to activatemore often than not. In contrast, some users may prefer the smart-homedevice to conserve energy and only activate the device when it is verylikely that the user intends to interact with the device.

Like other systems on the smart-home device, the motion signaturedetection and recognition algorithms can be learning algorithms thatdynamically update and store data in order to better recognize userintent. If a received motion signature matches a known motion signature,and the known motion signature indicates that the user intends tointeract with the device, the device may be activated. The indication ofuser intent stored with the known motion signature can be updated basedon whether the user actually interacts with the device. For example, ifthe user does not interact with the device, the algorithm can “punish”the motion signature by lowering the percentage indicating user intentto use. Similarly, if the user does interact with the device, thealgorithm can “reinforce” the motion signature by increasing thepercentage indicating user intent to use. Over time, the known motionsignature database for the smart-home device may grow to accuratelypredict user motion sequences that indicate an intent to use such thatpower conservation can be optimized and user experience can bemaximized.

By accessing the indication of intent to use stored with each knownmotion signature, the smart-home device can thus determine whetheraction should be taken (1808). If the intent to use indication is belowa threshold percentage or otherwise indicates that this motion signatureis not likely to indicate an intent to use, then the smart-home devicecan refrain from taking action by remaining in an inactive state (1810).On the other hand, when the intent use indication is above the thresholdpercentage or otherwise indicates that this motion signature is likelyto indicate an intent to use, the smart-home device can take action byactivating systems such as the user interface (1812).

FIG. 19 illustrates a flowchart 1900 of a method for continuouslyprocessing a motion signature after the smart-home device initiates aresponsive action, according to some embodiments. At this stage, it isassumed that the smart-home device has detected a motion signaturematching a known motion signature that indicates user intent to use. Byway of example, it is also assumed that the user interface of thesmart-home device is been activated in anticipation of the predicteduser interaction. However, in cases where the user changes their mind orotherwise deviates from the predicted action, not only will theprediction algorithm be retrained as described above, but correctiveaction can be taken by the smart-home device to reverse the activationof systems in response to the incorrect prediction, by, for example,turning off the user interface.

Normally, the user interface would stay on for an interval of 10 secondsto 30 seconds after being activated. In cases where the motion signatureincorrectly identified an intent to use, the user interface would stayactive for this entire interval even though the user never intended tointeract with the smart-home device. However, using the multi-channelnear-field proximity sensor described above, the smart-home device canquickly react to this situation in order to conserve energy and notdistract users. For example, the motion sequence ARR_L, ARR_R couldindicate that a user has approached the smart-home device from the left.Based on the recognition of this motion signature, and based on thehistorical training indicating that 75% of the time the user intendsinteract with the thermostat when approaching from the left, the userinterface can be activated.

At this point, the method may include detecting changes in the proximitysensor readings (1902). These changes may include specific channelresponses that indicate that the user is moving away from the device.For example, any of DEP_R, DEP_L, and/or DEP_C may indicate that theuser has moved away from the thermostat. If the changes in the proximitysensor readings indicate that the user is moving away from the device(1904), then corrective action can be taken. For example, the userinterface can be switched back to the inactive state immediately (1908).This capability allows the smart-home device to be very responsive whenthe user approaches the device by turning on a user interface, whilealso being very responsive when the user moves away. As soon as thesmart-home device recognizes that the user interface was activated inerror, the user interface will be deactivated. In some cases, the userinterface will display information, such as the temperature on thethermostat. When users walk towards the device they may simply want toknow the current setpoint temperature. This algorithm allows thesmart-home device to respond quickly and display information that isinformative to a user. When it is clear based on the channel readingsfrom the near-field proximity sensor that the user is moving away fromthe smart-home device, the user interface can be deactivated because itis unlikely that the user will use such information while walking awayfrom the smart-home device.

If the change does not indicate that the user is moving away from thedevice, then the user interface may be kept in the active state (1906).Channels on the sensor may generate responses that are not related tothe user. For example, another user may move within range of thesmart-home device, a user interacting with the smart-home device mayshift their body back and forth slightly between the left, right, andcenter responsive zones, and so forth. Unless the change in theproximity sensor readings clearly indicate that the user is moving awayfrom the smart-home device, the user interface can remain active toavoid the frustration of interrupting the user experience. Although notshown explicitly in FIG. 19, any input received through the userinterface of the smart-home device will also preclude turning off theuser interface, regardless of any change in the proximity sensorreadings.

In some embodiments, known changes to motion signatures may also bestored in a manner similar to how known motion signatures are stored.The changes detected in step 1902 may be compared to the known changesto motion signatures in order to determine whether they likely indicatethat the user is moving away from the device without an intent to usethe smart-home device further. This process of comparing, accessing athreshold probability, and taking an action in response may be carriedout as described above in relation to FIG. 7 for matching known motionsignatures and determining an intent to use.

It should be appreciated that the specific steps illustrated in FIGS.18-19 provide particular methods of processing movement/motionsignatures according to various embodiments of the present invention.Other sequences of steps may also be performed according to alternativeembodiments. For example, alternative embodiments of the presentinvention may perform the steps outlined above in a different order.Moreover, the individual steps illustrated in FIGS. 7-8 may includemultiple sub-steps that may be performed in various sequences asappropriate to the individual step. Furthermore, additional steps may beadded or removed depending on the particular applications. One ofordinary skill in the art would recognize many variations,modifications, and alternatives.

FIG. 20 illustrates a second mode of operation for the near-fieldproximity sensor during a user interactive session, according to someembodiments. After receiving user input through the user interface, suchas the rotatable ring 2004 around a smart-home device 2002, themulti-channel near-field proximity sensor can transition into a secondmode of operation. Alternatively, instead of requiring a user inputthrough the user interface, some embodiments may detect close proximitythrough the multi-channel proximity sensor or may simply detect a strongresponse on multiple channels, indicating that the user is standing nextto the smart thermostat. In this mode, motion inputs received caninstead be used to navigate through a user interface of the smart-homedevice. For example, when a user waives their hand 2010 in aright-to-left motion 2012, this will generate responses on first theright channel of the proximity sensor, then the left channel of theproximity sensor. It is likely that the entire motion will generate aresponse on the center channel.) This motion can be used to navigateback and forth through different menus. Similarly, up-and-down motion ofthe user's hand 2010 would generate responses on the up channel and thedown channel of the proximity sensor. This would be interpreted asscrolling within options 2008 of the current menu 2006. In someembodiments, rotating the hand around in a circular motion would insequence generate responses on the up channel, the left channel, thedown channel, the right channel, and so forth. The circular motion wouldbe interpreted by the smart-home device 2002 as an input similar torotating the rotatable ring 2004. This could be used toincrease/decrease the temperature of the current thermostat setpoint.Using hand gestures such as these may be beneficial for users witharthritis or other health-related issues that may make manipulating amechanical user interface difficult. Gestures such as these can also beuseful when users are unable to stay in front of the thermostat duringthe entire interactive session.

The up/down/left/right/circular hand gestures described above are merelyexemplary and not meant to be limiting. Other hand gestures may be used,where the hand of the user acts as an “air mouse.” Some embodiments mayalso use the Z axis emanating outward from the thermostat as an input,such that a user could push their hand towards the thermostat toindicate a “pushing a button in the air” type of input. While operatingin this mode, the sensors would not necessarily require certainthresholds, but could instead compare relative responses on varioussensor channels. For example, logic could detect when the left sensorsees more responsive energy than the other three sensors, indicatingthat the user's hand is raised to the left.

FIG. 21 illustrates a flowchart 2100 of a method for interpreting andgestures using the multi-channel proximity sensor, according to someembodiments. The method may include detecting an interaction with thedevice user interface (2102). This interaction with the user interfaceelement, such as a rotatable ring, a click device, and/or the like, cansignify to the smart-home device that inputs received from thenear-field proximity sensor should be interpreted as commands ratherthan interpreted as part of a motion signature indicating user movement.At this point, the smart-home device knows that the user is intending tointeract with the device, so it is able to transition into this new modeof operation without misinterpreting user intent.

The method may also include detecting proximity sensor zone movementduring the interaction with the device (2104). As described above, thiszone movement may include sequential triggering of the left zone and theright zone, sequential triggering of the up zone and the down zone, orsequential triggering of all four zones indicating a circular motion. Itwill be understood that these types of zone movement and hand gesturesare merely exemplary and used to illustrate the larger body of handgestures that can be used to control the smart-home device. Therefore,one having skill in the art will understand in light of this disclosurethat other hand gestures may be used as dictated by the layout of theparticular user interface. For example, some user interfaces may use adiagonal scrolling motion instead of a circular scrolling motion, whichwould be represented by a sequential triggering of the left/up zonesfollowed by the right/down zones.

In a manner similar to detecting known motion signatures, the zoneresponses during the interactive user interface session can be comparedto known zone responses indicating hand gesture commands (2106). Asdescribed above, a database of known hand gestures can be downloadedfrom the central management server, learned from user training sessions,and/or automatically observed through historical interactions with oneor more users. If the observed zone movements matches a known handgesture, then the known hand gesture can be interpreted as a command,and changes can be made to the user interface according to the handgesture (2110). Alternatively, if the zone movement does not match anyknown and gestures corresponding to user interface commands, thesmart-home device can disregard the movement (2108). Alternatively, thesmart-home device can transition back into the previous mode ofoperation where the multi-channel near-field proximity sensor interpretszone responses as user movements and generates motion signatures. Thissituation can arise when users end their interactive session with thethermostat and walk away.

It should be appreciated that the specific steps illustrated in FIG. 21provide particular methods of interpreting gestures according to variousembodiments of the present invention. Other sequences of steps may alsobe performed according to alternative embodiments. For example,alternative embodiments of the present invention may perform the stepsoutlined above in a different order. Moreover, the individual stepsillustrated in FIG. 21 may include multiple sub-steps that may beperformed in various sequences as appropriate to the individual step.Furthermore, additional steps may be added or removed depending on theparticular applications. One of ordinary skill in the art wouldrecognize many variations, modifications, and alternatives.

FIG. 22 illustrates using data from more than one smart-home device totrack user movements, according to some embodiments. The smart homeenvironment will typically include more than one smart-home device. Forexample, a hazard detector 2202 and the thermostat 2204 may be installedin the same room. Often times, users will install the thermostat 2204vin their hallway somewhat beneath a location where their hazarddetector 2202 is installed. Each smart-home device may be equipped withits own proximity sensor(s). When the fields of two or more proximitysensors on multiple devices overlap, the channel response informationcan be transmitted from one device to the other. This information can beused to reinforce the interpretation of motion signatures by one or moredevices.

In some embodiments, a first user may approach the thermostat 2204 inorder to interact with the user interface. The thermostat 2204 may beginreceiving responses from various channels of the multi-channel proximitysensor indicating the approach of the first user. At the same time, asecond user may also enter the field of view of the multi-channelproximity sensor of the thermostat 2204. In some cases, such a situationmay present confusing results to the thermostat 2204. Multiple users mayappear as a single user that is not approaching the thermostat 2204.However, proximity sensor responses from the hazard detector 2202 may beused to interpret ambiguous results received by the thermostat 2204. Forexample, if the first user 2206 is in the field of view of the hazarddetector 2202 and the second user (not shown) is out of view of thehazard detector 2202, then the motion signature of the first user 2206will be unambiguous as seen by the hazard detector 2202. The hazarddetector 2202 would see a motion signature of the first user 2206approaching the thermostat 2204. The hazard detector 2202 could thentransmit this information to the thermostat 2204 over a local smart-homedevice network. Using this information, the thermostat 2204 coulddisregard proximity sensor zone responses that do not agree with themotion signature received from the hazard detector 2202. In this manner,the thermostat 2204 may isolate the movement of the first user 2206while disregarding movement of the second user (not shown).

In other embodiments, the proximity sensor readings from othersmart-home devices can be used to determine an auto-away status for thethermostat 2204. In some installations, the thermostat 2204 may belocated in areas that are not subject to frequent traffic when the homeis occupied. For example, the thermostat 2204 may be installed at theend of a hallway, or in an unoccupied room. Because the thermostat 2204in such a location will not see user movements using its proximitysensors (near-field and/or far-field), the thermostat 2204 mayerroneously enter an auto-away mode. However, because the thermostat2204 is in communication with other smart-home devices, such as a hazarddetector 2202, the other smart-home devices can share occupancyinformation across the smart-home network.

Automatic Display Adjustment Based on Viewer Location

In the examples described above, the responses generated by thefar-field proximity sensor and the near-field proximity sensor are usedto activate a user display on a smart-home device. In addition to merelyactivating a user interface, some embodiments may offer moresophisticated and advanced user interface features that depend on theresponses generated by these two proximity sensors. Depending on auser's velocity, motion path/signature, identity, and/or distance fromthe smart-home device, the user interface can be modified to displayinformation that would be meaningful and useful for users in eachsituation.

FIG. 23 illustrates a diagram 2300 of different user positions relativeto a smart-home device 2314, according to some embodiments. Theresponsive ranges are illustrated as concentric circles for explanatorypurposes only. Actual responsive ranges may be oval, oblong, parabolic,and/or the like, depending on the particular hardware sensor chosen.User 2302 is outside of region 2310 and is thus considered to be out ofrange of all proximity sensors on the smart-home device 2314. Generally,when the user 2302 is out of range, the user interface of the smart-homedevice 2314 will be deactivated, in a sleep mode, or “off” When the user2302 is far enough away from the smart-home device 2314 that he/she isnot detected by the far-field proximity sensor, the user 2302 isgenerally also far enough away that information displayed on the userinterface of the smart-home device 2314 would be too small to read.However, some embodiments may use other smart-home devices within theenclosure (e.g., a hazard detector, a smart appliance, a wireless modulein a security system, etc.) in order to detect the presence of user 2302even outside the range of the far-field proximity sensor of thesmart-home device 2314. Therefore, some embodiments may activate theuser interface of the smart-home device 2314 to display information eventhough the user 2302 is a great distance away and otherwise undetectableby the smart-home device 2314 alone.

As a user 2304 moves within the range of the far-field proximity sensor,some embodiments may activate the user interface and display informationin a far-field setting. The information displayed while the user is inthe far-field region 2310, may be displayed in a large font size, usinghigh contrasting colors, or in a manner where substantially all of theuser interface area is used by the display. In some embodiments, iconsor graphics may be displayed on the user interface to grab the attentionof the user without displaying textual/numerical information that wouldfrustrate users being too far away to read it properly. Examples offar-field displays will be discussed in greater detail below.

As the user 2306 enters into the near-field range 2312, and thusgenerates a response on the near-field proximity sensor, the userinterface of the smart-home device 2314 can change the display into anear-field setting. In some embodiments, the near-field graphicaldisplay may include smaller fonts, menu options, textual/numericalinformation, and/or other information that would be more useful to auser 2306 in close proximity to the smart-home device 2314. In someembodiments, the near-field display and the far-field display may showgenerally the same information in different formats. For example thefar-field display may include an enlarged digital clock display, whilethe near-field display may include a more detailed analog clock display.In some embodiments, the far-field display includes a subset ofinformation that would be displayed in the near-field display. Forexample, the far-field display may include an alert icon, while thenear-field display would include the alert icon populated with textualinformation.

As illustrated by FIG. 23, some embodiments may have at least threedifferent display options: and off display, a far-field display, and anear-field display. As the user moves between responsive areas of thevarious proximity sensors of the smart-home device 2314, the userinterface can transition between each display in a correspondingfashion. Thus a processing transition can exist between each of theresponsive regions of the proximity sensors. The transition between theoff display and the far-field display can occur when the smart-homedevice 2314 begins receiving responses from the far-field proximitysensor. Similarly, the transition between the far-field display of thenear-field display can occur when the smart-home device 2314 begins toreceive responses from the near-field proximity sensor.

FIG. 24 illustrates a flowchart 2400 of a method for generating andtransitioning between various graphical displays on a user interface ofa smart-home device, according to some embodiments. The method mayinclude receiving an indication from a far-field proximity sensor(2402). Receiving an indication from the far-field proximity sensor mayoccur when a user enters the responsive range of the far-field proximitysensor. At this point, some embodiments of the smart-home device mayrecognize the need to activate the user interface. In order to determinethe type of information to display on the user interface, the smart-homedevice can analyze responses generated by both the near-field proximitysensor and the far-field proximity sensor together.

The method may further include determining whether an indication hasbeen received from the near-field proximity sensor (2404). If noindications have been received from the near-field proximity sensorwithin a predetermined time interval, the user interface can display afar-field display (2406). This situation will occur when a user is inrange of the far-field proximity sensor, but out of range of thenear-field proximity sensor. Note that it is not required forindications to be received from the near-field proximity sensor and thefar-field proximity sensor at precisely the same time. Instead, someembodiments will analyze time intervals, such as 10 ms, 50 ms, 100 ms,500 ms, 1 s, etc., and determine whether indications have been receivedfrom both proximity sensors within that time interval. Some embodimentsmay also begin a time interval when an indication is received from oneof the two proximity sensors, and look for an indication received fromthe other of the proximity sensors within that time interval. Forexample, if the far-field proximity sensor generates a response, thiswould begin a 100 ms time interval. The processing system of thesmart-home device would then monitor the near-field proximity sensor todetermine whether that sensor also generated a response within the 100ms time interval. If indications from both the far-field proximitysensor and the near-field proximity sensor are generated within the sametime interval, then the user interface can be caused to display thenear-field display (2408).

Although not shown explicitly in flowchart 2400, some situations mayoccur when a response is generated by the near-field proximity sensorwithout a corresponding response being generated by the far-fieldproximity sensor. For example, in cases where the far-field proximitysensor is not functioning or is obscured, the near-field proximitysensor may be the only proximity sensor generating response. In thiscase, when an indication is received from the near-field proximitysensor, the user interface can display the near-field display withoutrequiring an indication from the far-field proximity sensor.

FIG. 25A illustrates an example of a near-field display 2502 of athermostat function, according to some embodiments. The near-fielddisplay 2502 includes information that will be both useful and readableby users in the near-field range. For example, the near-field display2502 may include an indication of the current temperature (75°), adescription of a current HVAC function (“heating”), tick marks around acircular periphery of the user interface indicating degree increments,and enlarged tick marks showing both a current temperature and asetpoint temperature. This information may be considered more usefulwhen the user is close to the smart-home device. When a user is close,it may indicate an intent to use or interact with the smart-home device,therefore it may be preferential to display information that would aid auser in such interaction. For example, as a user intends to interactwith a thermostat, the user will need to know information such as acurrent temperature, setpoint temperature, a difference between thecurrent temperature and the setpoint temperature, an HVAC function, andso forth. This information may also be considered more appropriatelysized for a nearby user. It is unlikely that a user 12 to 15 feet awaywould be able to decipher the individual tick marks or to read the HVACfunction. By displaying this information when the user is farther away,it may lead to user frustration and make them move closer to thesmart-home device just to read the information. However, displaying thisinformation when a user is nearby may provide all the useful informationa user would need to know about the thermostat function withoutrequiring interaction with the user interface.

FIG. 25B illustrates an example of a far-field display 2504 of thethermostat function, according to some embodiments. The far-fielddisplay 2504 includes a subset of the information of the near-fielddisplay 2502. In this case, only the current temperature is displayed.The far-field display 2504 also enlarges the display size of the subsetof information. Here, the font size of the current temperature (75°) isenlarged to substantially fill the area of the user interface. The fontsize can be increased until the text would begin to move off of the userdisplay. As a user moves from the responsive area of the far-fieldproximity sensor into the responsive area of the near-field proximitysensor, the thermostat user interface can transition from the far-fielddisplay 2504 to the near-field display 2502, and vice versa.

FIG. 26A illustrates an example of a near-field display 2602 of a clockfunction, according to some embodiments. The near-field display 2602comprises an analog clock graphic with the minute hand, second hand, andhour hand that can be digitally simulated to move around a circular userinterface in the same fashion as a traditional mechanical clock. Becauseof the fine detail and the small size of the numbers and clock hands,the near-field display 2602 may be appropriate for nearby users and mayprovide a warm and familiar ambience. FIG. 26B illustrates an example ofa far-field display 2604 of the clock function, according to someembodiments. The far-field display 2604 includes the same information(i.e. time of day) as the near-field display 2602, just in a differentformat. Here, the time of day it is displayed in a digital clock formatwith that is enlarged to fill the user interface. Although the far-fielddisplay 2604 does not convey as much information as the near-fielddisplay 2602 (e.g., second information), the far-field display 2604 maybe easily viewed from a greater distance. As described above, the userinterface of the smart-home device can transition between the near-fielddisplay 2602 and the far-field display 2604 as the user moves betweenthe responsive area of the near-field proximity sensor and theresponsive area of the far-field proximity sensor.

FIG. 27A illustrates an example of a near-field display 2702 of an alertfunction, according to some embodiments. The near-field display 2702illustrates a graphical icon that visually conveys to a user the factthat the smart-home device is generating an alert. An alert may indicatean HVAC system problem, a message sent from a central management server,a severe weather warning from a local weather service, a demand-responseevent in which the user can choose to participate, a warning that theuser has surpassing an expected or maximum power usage for the month, ahumidity warning, a freeze warning, and so forth. From a distance, thefar-field display 2702 only needs to indicate the fact that an alert hasbeen received by the smart-home device. In order to see the details ofthe alert, the user may move closer to the smart-home device and intothe responsive range of the near-field proximity sensor. FIG. 27Billustrates a near-field display 2704 of the alert function, accordingto some embodiments. As the user moves closer to the smart-home device,the near-field display 2704 can populate the graphical icon with textualinformation describing the alert. In the example of FIG. 27B, the alerticon has been populated with an indication that an alert has beenreceived from a central management server. Additionally, as the usermoves closer to the smart-home device, the graphical icon can bepopulated with menu options. For example, the user can be presented withmenu options to either read the alert or to ignore the alert. In someembodiments, the details of the alert can be displayed automatically onthe user interface without requiring interaction with menu items. Insome embodiments, if the user moves from the responsive range of thefar-field proximity sensor into the responsive range of the near-fieldproximity sensor, and the user interface is populated with the detailsof the alert as described above, the smart-home device may determinethat the user has read the details of the alert. If the user thensubsequently moves away from the device and out of the responsive rangeof near-field proximity sensor, the smart-home device can dismiss thealert under the assumption that it was read by the user when theyapproached the smart-home device.

FIG. 28 illustrates a flowchart 2800 of a method of usingcharacteristics of user motion to generate and control user interfacedisplays, according to some embodiments. In the embodiments describedabove, the transitions between a far-field display and a near-fielddisplay may be described as binary, i.e. the display type may be changedbased at least in part on a single transition between the responsiveareas of different proximity sensors. However, as described above, someembodiments of a smart-home device may include a multi-channelnear-field proximity sensor with two or more overlapping responsiveranges. By analyzing the responses generated by individual channels,more information can be gleaned about the motion signature of the user.For example, an approximate velocity can be determined, a motiondirection can be determined, and/or the like. By detecting acharacteristic of the user's motion, this information can be used to notonly activate a user display and transition between possible displays,but to also incrementally change the user display in response to thedetected motion characteristics.

The method may include receiving an indication from the near-fieldproximity sensor (2802). The indication may be part of one or moreresponses generated by one or more channels of the near-field proximitysensor. For example, the indication may include an arrival response fromthe left channel followed by an arrival response from the right channelof the near-field proximity sensor. The method may additionally includedetecting a characteristic of the motion detected by the near-fieldproximity sensor (2804). As described above, some embodiments maydetermine a motion signature that is based on the sequence and/or timingof different channel responses. For example, a user may move from leftto right in front of the smart-home device, or user may directlyapproach the smart-home device. In these embodiments, the motionsignature may be considered the motion characteristic. In otherembodiments, the motion characteristic may include a relative speed ofthe user. For example, if the average width of the left channel beforeit is overlapped by the right channel is approximately 6 feet, theapproximate speed of the user may be calculated by dividing thisdistance by the time delay between responses of the left channel and theright channel. When approaching the smart-home device directly, thespeed may be determined by dividing the width between the far-fieldresponsive area and the near-field responsive area by the time betweenresponses from the two proximity sensors. In these embodiments, thevelocity may by itself be considered the motion characteristic, and/orthe velocity and the motion signature may be considered the motioncharacteristic in combination.

In some embodiments, a user identity may be determined from theproximity sensors. The user identity may be specific to an individual(e.g. Geddy versus Alex), or the user identity may indicate a specificclass of users (e.g. adults versus children). For specific individuals,a motion signature may be recognized by the smart-home device andattributed to a particular user. For example, if a home includes twousers, and one of the users moves faster than the other user, anestimated velocity of travel as determined by the multi-channelproximity sensor may be used to identify the user. In other embodiments,each user may be associated with their own control schedule. Forexample, a first user may be home during daytime hours, while a seconduser may be home during nighttime hours. When a user is detected withinthe range of the proximity sensors of the smart-home device, the controlschedules can be accessed and a user can be determined by ascertainingwhich user should be home according to the control schedules. In otherembodiments, the user identities may be transmitted to the smart-homedevice by other devices in a smart home network. In some embodiments,electronic devices carried by the users may be used to identify users.For example, an application operating on the smart phone of a user canuse GPS information to transmit an approximate location to thesmart-home device. RFID tags may be used in another example. Thesmart-home device can then use the GPS/RFID information and/orinformation from the onboard proximity sensors to determine a useridentity. Other embodiments may use Bluetooth low energy (BLE) or Wi-Fiemissions from cell phone in order to differentiate users.

Some embodiments can distinguish a class of individuals rather thanidentifying specific identities. For example, a multi-channel proximitysensor with an up channel and a down channel may be used to discriminatebetween adults and children based on height. Children are generallyshorter, and will result in a strong response on the down channel of theproximity sensor while generating a smaller response from the up channelof the proximity sensor. In contrast, adults are generally taller thanthe children, and will result in a more equal response between the downchannel and the up channel (taking into account any scaling of the downchannel to eliminate pet detections). The smart-home device may providedifferent displays based on whether a detected user is a child or anadult. For example, children are typically uninterested in interactingwith the smart-home device, and adults would generally prefer thatchildren do not interact with their smart-home device. Therefore, thesmart-home device may leave the user interface off when a child isdetected, and provide one of the other user interfaces described hereinwhen an adult is detected. Additionally, the down channel of theproximity sensor will generate a larger response for pets than the upchannel. When a pet is detected, the thermostat can disregard theassociated motion.

The method may also include determining whether the detected motioncharacteristic matches a predetermined characteristic (2806). Asdescribed above, the detected motion characteristic can be compared to adatabase of stored motion characteristics. For example, a sensed motionsignature can be compared to stored motion signatures. Characteristicsindicating a user identity can be compared to store characteristics thathave been previously associated with user identities. Velocities anduser sizes can be compared to previously recorded velocities and usersizes for particular users or user classes. The database of storedmotion characteristics can be downloaded from a central managementserver, learned during a training interval after installation of thesmart-home device, and/or updated dynamically over time as thesmart-home device records movements from users during normal operation.

The display of the user interface can be updated based on whether thesensed motion characteristic matches a predetermined motioncharacteristic. If a match is found, a first display can be displayed(2810). Alternatively, if no match is displayed, an alternative displaycan be displayed (2808). The alternative display or the first displaymay comprise an off state for the user interface. It will be understoodthat the two displays used in FIG. 28 are merely exemplary and not meantto be limiting. Other embodiments may use three or more displays thatmay change in increments as more information is received from the usermotion.

FIG. 29 illustrates a diagram 2900 of a progressive alert display,according to some embodiments. The multi-channel proximity sensor allowsthe smart-home device the ability to discern a motion signature that canindicate that the user is approaching the smart-home device. Such anapproach may indicate that the user intends to interact with thesmart-home device. Alternatively, such an approach may indicate that theuser would be susceptible a display indicating that he/she shouldinteract with the smart-home device. In either case, the smart-homedevice can use this information to provide progressively moreinformation on the user interface as the user draws near to thesmart-home device.

The following example assumes that an alert is being generated by thesmart-home device 2908. As the user enters the responsive range of thenear-field proximity sensor 2916 at position 2902, the smart-home device2908 can generate a display 2910 that shows the alert icon. As describedabove, the display at this range may have already been activated whenthe user entered the responsive range of the far-field proximity sensor.As the user moves closer to the smart-home device 2908 into position2904, the smart-home device 2908 may begin to receive responses fromadditional channels of the multi-channel proximity sensor indicatingthat the user is moving towards the smart-home device 2908. For example,both the center (up/down) and the right channel may generate responseswhen the user is in position 2904. At this point, the smart-home device2908 can determine that the user may at least be susceptible to apresentation of more information regarding the alert. In response, thesmart-home device 2908 can present display 2912 which begins to populatethe alert icon with textual information describing the alert. In thisexample, the textual information can describe how an alert is beenreceived from a central management server.

As the user continues to move closer to the smart-home device 2908,additional channels of the multi-channel proximity sensor will generateresponses (e.g., the left, right, and center channels may begin togenerate responses). Additionally, the response level of each channelmay increase in magnitude above a threshold amount indicating that theuser is close to the smart-home device 2908 (e.g., the “approach”threshold described above). As the user draws within an interactivedistance of the smart-home device 2908, display 2914 can be generatedwhich will provide textual information and menu options for the alert.By gradually increasing the amount of information displayed by thesmart-home device 2908, the user interface can both entice the user tocontinue moving towards the smart-home device 2908 and present the userwith information that is readable and relevant according to theirdistance from the smart-home device 2908. Particularly in the case of analert, it may be desirable for the smart-home device 2908 to entice theuser to interact with the smart-home device 2908 such that the alert canbe read and responded to.

Although not shown in FIG. 29, alternative displays can also begenerated when the smart-home device 2908 determines that the user isnot responding to the existing user display and moving away from thesmart-home device 2908. For example, if the user at position 2902 doesnot progress towards the thermostat in response to display 2910 of thealert icon (e.g., the user moves to the left instead of towards thesmart-home device 2908), the smart-home device 2908 can generate adisplay that is configured to attract the user's attention. For example,display 2910 can be modified such that the alert icon begins to flash orchange colors. If the motion signature of the user continues to indicatethat the user is ignoring the smart-home device 2908, the user interfacecan be turned off in some embodiments.

FIG. 30 illustrates a diagram 3000 of a progressive user interface basedon user identities, according to some embodiments. Once users enter theresponsive area 3010 of the near-field proximity sensor, the multiplechannels of the sensor can be used to distinguish between differentusers as described above. In this example, the multi-channel proximitysensor can discriminate between a child and an adult based on height. Asa child 3004 walks by the smart-home device 3010, the smart-home device3010 can generate display 3006 showing the time of day in a digitalfashion. This type of display will be easy to read for a child and thedigital display will be more familiar to a child than that of the moretraditional analog display that would be familiar to an adult.

When an adult 3002 passes by the smart-home device 3010, a display canbe generated that is more appropriate for an adult. In this example,display 3008 can be generated to show an alert to the adult 3002 thatwould normally be hidden from the child 3004. In other embodiments, auser identity can be determined by other means to distinguish betweenindividual users. For example, a user designated as a primary user(e.g., a user responsible for paying the energy bills) may be providedwith display 3008, while a user designated as a secondary user (e.g., aroommate) may be provided with display 3006 based on their identities.

Different user displays can also be displayed to users based on theiridentities based on stored user profiles. For example, a first user mayprefer the analog clock display, while a second user may prefer thedigital clock display. A user profile may also indicate one user in thehousehold (e.g., a head of the household) as one responsible forreceiving alerts and HVAC system messages.

FIG. 31 illustrates a diagram 3100 of progressive user displays based onuser velocities, according to some embodiments. The speed with which auser travels by the smart-home device 3110 may at least in part indicatehow susceptible the user will be to interactive displays or displaysthat require more user attention. For example as a user 3106 passes bythe smart-home device 3110 at a velocity that is below a predeterminedthreshold, the smart-home device 3110 may determine that the user mayrespond to information displayed on the user interface. Exemplarydisplay 3108 may be provided that includes alert information and/or menuoptions with which the user 3106 may interact. Alternatively, if a user3102 is passing by the smart-home device 3110 at a velocity greater thanthe predetermined threshold, the user interface can provide a display3104 that, while possibly informative, does not require user interactionor attention.

FIGS. 32A-32D illustrate user interface displays that are part of aprogressive animation that may be displayed when the user interface isactivated. As described above, the user interface of the smartthermostat may activate when a user approaches the responsive range ofthe far-field proximity sensor and/or the near-field proximity sensor.When the user walks by the smart thermostat, it may be desirable todisplay graphics on user interface that are calculated to attract theattention of the user who only sees the thermostat in the periphery ofhis/her vision. In some embodiments, when the user interface isactivated, the display can start small and, in an animated fashion,grown larger. After reaching an oversized size, the graphics can shrinkslightly to a normal size. This animated transition from small, tolarge, and back to a normal size results in an animation that causes thegraphics to “pop” towards the user. Sudden motion such as this has beenfound to attract the attention of users as they walk by the thermostat.This can be particularly useful when messages or alerts are to bedisplayed on the user interface. FIG. 32A illustrates a starting sizefor an animation that displays the current time for the user. Thecurrent time can continuously grow to an intermediate size asillustrated by FIG. 32B, and then to an oversized size as illustrated byFIG. 32C. The current time can then shrink back down to a normal size asillustrated by FIG. 32D. the “normal size” may be the size at which thecurrent time will be displayed in a steady state after the animation iscomplete. In some embodiments, the entire animation process may takeless than one second to transition from a blank display to that of FIG.32D.

In some embodiments, the user interface can display graphics thatprovide information to user as they approached the thermostat, such as acurrent time, a current temperature, an alert, and/or the like. Thisinformative display can remain active on user interface until the userinteracts with the thermostat. As described above, some embodiments cantransition to a menu display when the user comes within a very closeproximity to the thermostat. In other embodiments, the informativedisplay can stay active on the user interface until the user actuallyinteracts with the thermostat, e.g., by rotating or clicking the outerrotatable ring or other user interface elements.

Implementation of the techniques, blocks, steps and means describedabove may be done in various ways. For example, these techniques,blocks, steps and means may be implemented in hardware, software, or acombination thereof. For a hardware implementation, the processing unitsmay be implemented within one or more application specific integratedcircuits (ASICs), digital signal processors (DSPs), digital signalprocessing devices (DSPDs), programmable logic devices (PLDs), fieldprogrammable gate arrays (FPGAs), processors, controllers,micro-controllers, microprocessors, other electronic units designed toperform the functions described above, and/or a combination thereof.

Also, it is noted that the embodiments may be described as a processwhich is depicted as a flowchart, a flow diagram, a data flow diagram, astructure diagram, or a block diagram. Although a flowchart may describethe operations as a sequential process, many of the operations can beperformed in parallel or concurrently. In addition, the order of theoperations may be re-arranged. A process is terminated when itsoperations are completed, but could have additional steps not includedin the figure. A process may correspond to a method, a function, aprocedure, a subroutine, a subprogram, etc. When a process correspondsto a function, its termination corresponds to a return of the functionto the calling function or the main function.

Furthermore, embodiments may be implemented by hardware, software,scripting languages, firmware, middleware, microcode, hardwaredescription languages, and/or any combination thereof. When implementedin software, firmware, middleware, scripting language, and/or microcode,the program code or code segments to perform the necessary tasks may bestored in a machine readable medium such as a storage medium. A codesegment or machine-executable instruction may represent a procedure, afunction, a subprogram, a program, a routine, a subroutine, a module, asoftware package, a script, a class, or any combination of instructions,data structures, and/or program statements. A code segment may becoupled to another code segment or a hardware circuit by passing and/orreceiving information, data, arguments, parameters, and/or memorycontents. Information, arguments, parameters, data, etc. may be passed,forwarded, or transmitted via any suitable means including memorysharing, message passing, token passing, network transmission, etc.

While the principles of the disclosure have been described above inconnection with specific apparatuses and methods, it is to be clearlyunderstood that this description is made only by way of example and notas limitation on the scope of the present teachings.

What is claimed is:
 1. A thermostat comprising: a proximity sensor fordetecting user presence; a temperature sensor that provides temperaturemeasurements for calculating an ambient temperature in an areasurrounding the thermostat; a sensor mount assembly containing theproximity sensor and the temperature sensor, the sensor mount assemblyincluding a first alignment feature; a lens assembly comprising a firstarea, a second area, and a second alignment feature, wherein the secondarea comprises a Fresnel lens, and the first area is thinner than thesecond area; a front cover, wherein an outward-facing surface of thelens assembly is shaped to continuously conform to a curvature of thefront cover; and a frame member comprising third and fourth alignmentfeatures configured for respective matable alignment with the first andsecond alignment features and further configured such that the proximitysensor and the temperature sensor are maintained in generally close,non-touching proximity to the lens assembly, the first area of the lensassembly being aligned with the proximity sensor, and the second area ofthe lens assembly being aligned with the temperature sensor.
 2. Thethermostat of claim 1, wherein the sensor mount assembly comprises aflexible circuit board to which the proximity sensor and the temperaturesensor are mounted.
 3. The thermostat of claim 1, wherein the sensormount assembly further comprises a bracket comprising at least twodifferent elevations such that the proximity sensor and the temperaturesensor sit at the at least two different elevations relative to thelens.
 4. The thermostat of claim 1, wherein the temperature sensorcomprises an IC body and a metal pin through which the temperaturemeasurements for calculating the ambient temperature in the areasurrounding the thermostat are received, and wherein a portion of thesensor mount assembly is rotated at an angle such that the metal pin iscloser to the lens assembly than the IC body.
 5. The thermostat of claim1, wherein the sensor mount assembly further comprises a secondproximity sensor.
 6. The thermostat of claim 1, wherein the proximitysensor comprises a passive infrared (PIR) sensor, and the distancebetween the second area of the lens assembly and the PIR sensor isbetween 6 mm and 8 mm.
 7. The thermostat of claim 1, wherein the lensassembly is fabricated from a continuous piece of high-densitypolyethylene (HDPE) using an injection molding process.
 8. Thethermostat of claim 1, wherein the proximity sensor comprises amulti-channel thermopile comprising at least a left channel and a rightchannel.
 9. The thermostat of claim 1, wherein the distance between thetemperature sensor and the first area of the lens is less than 3 mm. 10.The thermostat of claim 1, further comprising electromagnetic shieldingthat wraps around the proximity sensor and around at least a portion ofthe sensor mount assembly.
 11. A method of aligning sensor and lenselements in a smart thermostat, the method comprising: providing asensor mount assembly comprising: a proximity sensor for detecting userpresence; a temperature sensor that provides temperature measurementsfor calculating an ambient temperature in an area surrounding thethermostat; and a first alignment feature; providing a lens assemblycomprising: a first area; a second area comprising a Fresnel lens,wherein the first area is thinner than the second area; and a secondalignment feature; providing a frame member comprising third and fourthalignment features configured for respective matable alignment with thefirst and second alignment features and further configured such that theproximity sensor and the temperature sensor are maintained in generallyclose, non-touching proximity to the lens assembly, the first area ofthe lens assembly being aligned with the proximity sensor, and thesecond area of the lens assembly being aligned with the temperaturesensor; connecting the sensor mount assembly to the frame member bymating the first alignment feature with the third alignment feature; andconnecting the lens assembly to the frame member by mating the secondalignment feature with the fourth alignment feature.
 12. The method ofclaim 11, wherein the sensor mount assembly comprises a flexible circuitboard to which the proximity sensor and the temperature sensor aremounted.
 13. The method of claim 11, wherein the sensor mount assemblyfurther comprises a bracket comprising at least two different elevationssuch that the proximity sensor and the temperature sensor sit at the atleast two different elevations relative to the lens.
 14. The method ofclaim 11, wherein the temperature sensor comprises an IC body and ametal pin through which the temperature measurements for calculating theambient temperature in the area surrounding the thermostat are received,and wherein a portion of the sensor mount assembly is rotated at anangle such that the metal pin is closer to the lens assembly than the ICbody.
 15. The method of claim 11, wherein the sensor mount assemblyfurther comprises a second proximity sensor.
 16. The method of claim 11,wherein the proximity sensor comprises a passive infrared (PIR) sensor,and the distance between the second area of the lens assembly and thePIR sensor is between 6 mm and 8 mm.
 17. The method of claim 11, whereinthe lens assembly is fabricated from a continuous piece of high-densitypolyethylene (HDPE) using an injection molding process.
 18. The methodof claim 11, wherein the proximity sensor comprises a multi-channelthermopile comprising at least a left channel and a right channel. 19.The method of claim 11, wherein the distance between the temperaturesensor and the first area of the lens is less than 3 mm.
 20. The methodof claim 11, wherein the sensor mount assembly further compriseselectromagnetic shielding that wraps around the proximity sensor andaround at least a portion of the sensor mount assembly.